As the world reacted Thursday to news of Queen Elizabeth II's death, some major landmarks began displaying tributes to Britain's longest-reigning monarch.

In Paris, Mayor Anne Hidalgo offered her city's "deep sorrow" to the British ambassador to France and said the Eiffel Tower lights would be extinguished Thursday night in tribute to the queen.

Video footage captured after dark showed the moment the Eiffel Tower's lights went out.

LIVE NOW: The Eiffel Tower will turn off its lights at midnight in homage to Queen Elizabeth II https://t.co/bRzLIIoZdl

In New York City, the Nasdaq headquarters building in Times Square displayed a photo of the queen and a message that read, "Nasdaq honors the life and legacy of Queen Elizabeth II."

Meanwhile, memorials that started in the UK earlier Thursday grew as mourners left flowers and other tokens of remembrance. As night fell in London, photographers captured images of crowds gathering to mourn outside Buckingham Palace.

The accession rules governing the British monarchy dictate that a new ruler rises to power upon the death of a reigning monarch. These rules mean that Charles, the oldest son of Queen Elizabeth II, became king the moment his mother died on Thursday.

The new monarch will officially carry out his duties as King Charles III. The king began taking on some of the responsibilities outlined in his new role before the queen's passing.

Now that Charles is king, lawmakers in Parliament must swear their allegiance to him, while King Charles III will be required to swear an oath of his own in front of the Privy Council at St. James's Palace, according to The Associated Press. A vow of his Protestant faith must also be sworn before Parliament.

Though Charles became king right away, the AP reported it could be several months before he is officially coronated.

Other titles in the royal family are also changing in the wake of the queen's death. Camilla, the wife of King Charles III, is becoming the Queen Consort. Prince William and his wife, Kate Middleton, have up until this point been the Duke and Duchess of Cambridge. They are now the Duke and Duchess of Cornwall and Cambridge, a change that was made Thursday evening on the couple's official social media accounts.

Former President Donald Trump released a statement Thursday evening about King Charles III, who is ascending the throne in the wake of his mother's death.

In a post on Truth Social, Trump said he has come to know the new British monarch "well" and predicted he will be "a Great and Wonderful King."

King Charles III "dearly loves the United Kingdom and all that it represents to the World," Trump's post said.

"He will prove to be an inspiration to everyone," the post continued. "Queen Elizabeth has been, and will be from above, very proud of King Charles III."

Earlier Thursday, Trump's office released a joint statement with former first lady Melania Trump that offered condolences to the royal family and to the UK at large.

The joint statement said in part that the queen "will always be remembered for her faithfulness to her country and her unwavering devotion to her fellow countrymen and women."

It also said the Trumps will "always cherish our time together with the Queen" and will "never forget Her Majesty's generous friendship, great wisdom, and wonderful sense of humor."

"What a grand and beautiful lady she was—there was nobody like her," the statement added.

UK Prime Minister Liz Truss has reportedly spoken with King Charles III in the wake of his mother's death on Thursday.

Truss, who is new to the prime minister role, addressed the public about Queen Elizabeth II's passing outside her office at 10 Downing Street in London Thursday evening. She met with the queen earlier this week as her new role within the British government was made official.

A Downing Street spokesperson told Reuters Truss spoke with the new king following her public remarks on Thursday.

Later Thursday evening, Truss released a statement that referred to the queen as "the rock on which modern Britain was built."

"Our country has grown and flourished under her reign," her statement said.

Former Prime Minister Boris Johnson said today is "our country's saddest day."

In a statement, Johnson said there is an ache in everyone's hearts over the passing of Queen Elizabeth II, "far more intense, perhaps, than we expected."

"She seems so timeless and so wonderful that I am afraid we had to come to believe, like children, that she would just go on and on," he said.

As the Commonwealth grieves, Johnson, who recently resigned as Prime Minister, said his thoughts are with the Royal Family.

Statement on the death of Her Majesty Queen Elizabeth II (1/3) pic.twitter.com/kDN6cW8Njp

Johnson said people around the world are facing the reality that the Queen is really gone.

"It is only really now that we grasp how much she meant for us, how much she did for us, how much she loved us," Johnson said.

"We think of her deep wisdom, and historic understanding, and her seemingly inexhaustible but understated sense of duty," he said. "Relentless though her diary must have felt, she never once let it show, and to tens of thousands of events - great and small - she brought her smile and her warmth and her gentle humour - and for an unrivalled 70 years she spread that magic around her Kingdom."

Johnson said the Queen had a "unique and simple power to make us happy" and noted her ability to modernize the monarchy and produce heirs that will honor her legacy.

He said the country will utter words it has not heard in more than seven decades: "God save the King."

Statement on the death of Her Majesty Queen Elizabeth II (3/3) pic.twitter.com/yHPiUfBWlH

Prince Harry has arrived at Balmoral Castle in Scotland after the death of his grandmother Queen Elizabeth II.

The Duke of Sussex, along with his with Meghan Markle, stepped down as senior working royals and moved to North America in 2020.

Harry and Meghan were in the United Kingdom and were set to attend a charity event this evening in London.

The Duke of Sussex photographed arriving at Balmoral this evening (📷 Andrew Milligan/PA Wire) pic.twitter.com/YPW09PTKoy

Harry arrived alone, without Meghan, after his brother, Prince William, and his uncles, Prince Edward and Prince Andrew, arrived hours earlier.

He was photographed arriving in darkness more than an hour after the official announcement was released to the media at 6.30 p.m. U.K. time. He was seen with his head in his hands as his car arrived in the rain to the castle.

People across the United Kingdom were seen grieving on Thursday in the wake of Buckingham Palace's announcement that Queen Elizabeth II had died.

Video captured by BBC News showed hundreds of people gathered outside Buckingham Palace in London, where crowds began to amass earlier in the day as word spread that the queen was under medical supervision. Her death was announced Thursday evening.

Crowds have gathered outside Buckingham Palace following the announcement that Queen Elizabeth II has diedhttps://t.co/RnMJqFiOgK pic.twitter.com/V4A6iTtH04

Photos taken at Buckingham Palace showed some mourners leaving flowers at the palace gates.

Bouquets of flowers were also left by members of the public outside the Balmoral Estate in Scotland.

Others laid flowers in the queen's memory at the Palace of Holyroodhouse in Edinburgh, Scotland.

Additional floral tributes were photographed lining the gates outside Windsor Castle.

Across the Atlantic Ocean, people also began leaving flowers outside the British Embassy in Washington, D.C.

Flags flying over royal palaces have been lowered to half-staff to honor the passing of Queen Elizabeth II.

The Union Flag at Buckingham Palace was lowered shortly after her death was announced.

A notice was also placed on the gates of the palace with the official announcement of the Queen's death.

At Westminster Abbey, the flag was also lowered, as members of Parliament mourn the Queen's death.

A real sense of unanchoring here in Westminster as flags are lowered to half mast. The vast majority of us have lived our lives as Elizabethans without really thinking about it. #QueenElizabeth pic.twitter.com/zrvCzllTqJ

As the Union Flag was lowered at Windsor Castle, a rainbow briefly appeared over the royal residence.

Across the pond, the U.S. government is also honoring the loss of the Queen.

The American flag was lowered to half-staff over the U.S. Capitol Building after the news of her passing.

In an official proclamation, President Joe Biden ordered that all American flags at the White House to be flown at half-staff until sunset "as a mark of respect for the memory of Queen Elizabeth II."

This includes American flags upon all public buildings and grounds, at all military posts and naval stations and on all naval vessels of the federal government in D.C. and throughout the United States.

"I also direct that the flag shall be flown at half-staff for the same length of time at all United States embassies, legations, consular offices, and other facilities abroad, including all military facilities and naval vessels and stations," Biden said.

U.S. President Joe Biden said Queen Elizabeth "defined an era."

"Her Majesty Queen Elizabeth II was more than a monarch," he said in a lengthy statement. "She defined an era."

Biden said the Queen was a "steadying presence and a source of comfort and pride" for generation is a "world of constant change."

He acknowledged that many people in Great Britain "have never known their country without her."

"An enduring admiration for Queen Elizabeth II united people across the Commonwealth," Biden said. "The seven decades of her history-making reign bore witness to an age of unprecedented human advancement and the forward march of human dignity."

Our statement on the death of Queen Elizabeth II. pic.twitter.com/0n7pmVVg2w

Biden said Queen Elizabeth was the first British monarch "to whom people all around the world could feel a personal and immediate connection" and said she "dedicated her whole life to their service."

Queen Elizabeth II "led always with grace, an unwavering commitment to duty, and the incomparable power of her example," Biden said, noting her strength through World War II and a global pandemic and her dedication to several charities and patronages.

Biden first met the Queen in 1982 when traveling to the United Kingdom as part of a Senate delegation. The last time the president met with the Queen was in June 2021 in his first oversees trip as president.

"Queen Elizabeth II was a stateswoman of unmatched dignity and constancy who deepened the bedrock Alliance between the United Kingdom and the United States," he said. "She helped make our relationship special."

Biden said his thoughts and prayers are will the people of the United Kingdom and the Commonwealth.

"Her legacy will loom large in the pages of British history, and in the story of our world," he said.

Canadian Prime Minister Justin Trudeau released a statement on social media in memory of Queen Elizabeth II, who died at age 96 on Thursday.

Trudeau said news of the queen's passing was received "with the heaviest of hearts" in Canada.

"She was a constant presence in our lives – and her service to Canadians will forever remain an important part of our country's history," Trudeau said.

"As we look back at her life and her reign that spanned so many decades, Canadians will always remember and cherish Her Majesty's wisdom, compassion, and warmth," his statement continued. "Our thoughts are with the members of the Royal Family during this most difficult time."

In public remarks delivered in Vancouver, Trudeau expanded on his initial statement about the queen's death.

"In a complicated world, her steady grace and resolve brought comfort and strength to us all," he said. "Canada is in mourning. She was one of my favorite people in the world, and I will miss her so."

It was with the heaviest of hearts that we learned of the passing of Canada’s longest-reigning Sovereign, Her Majesty Queen Elizabeth II. She was a constant presence in our lives – and her service to Canadians will forever remain an important part of our country’s history.

Newly-appointed Prime Minister Liz Truss said Queen Elizabeth II "was the rock on which modern Britain was built."

During a statement outside of Downing Street, Truss said "Britain is the great country it is today because of her."

Truss said Queen Elizabeth ruled for 70 years will "dignity and grace" as she champion the growth of the Commonwealth and built "a modern, thriving, dynamic nation."

"Through thick and thin, Queen Elizabeth II provided us with the stability and the strength that we needed," Truss said. "She was the very spirit of Great Britain, and that spirit will endure."

Truss said she is "devastated" by the news of the loss of the Queen and called today a "great loss" as the Queen leaves a "great legacy" behind.

The Queen was loved by millions around the world and was a personal inspiration to Truss personally. Just days ago, the Queen appointed Truss the new Prime Minister of the United Kingdom.

Her Majesty Queen Elizabeth II pic.twitter.com/Acp3xy5kH4

The Prime Minister also offered her "loyalty and devotion" to Prince Charles, who she referred to as King Charles III.

"Today the crown passes, as it has done for more than a thousand years, to our new monarch, our new head of state," she said.

She said the nation will support him as he will "usher in a new era" for the country after the passing of the second Elizabethan Age.

"God save the King," Truss said, ending her statement.

The Prime Minister’s statement on the death of Her Majesty The Queen. pic.twitter.com/CwxGL1N74h

The Royal Family released a statement from Charles on Thursday that addressed the passing of his mother, Queen Elizabeth II.

The statement was attributed to "His Majesty the King." Charles is first in the line of succession and will now take on the role as Britain's monarch.

The queen's death "is a moment of the greatest sadness for me and all members of my family," the king's statement said.

"We mourn profoundly the passing of a cherished Sovereign and a much-loved Mother. I know her loss will be deeply felt throughout the country, the Realms and the Commonwealth, and by countless people around the world," his statement continued.

As the grieving process begins, "my family and I will be comforted and sustained by our knowledge of the respect and deep affection in which The Queen was so widely held," he said.

A statement from His Majesty The King: pic.twitter.com/AnBiyZCher

As crowds gathered outside Buckingham Palace, photos and videos began to emerge of a double rainbow that appeared near the palace Thursday evening.

Videos shared on social media showed that the double rainbow could be seen by people who were standing with their backs to the palace. Many had gathered beneath umbrellas throughout the rainy afternoon in anticipation of news about the queen.

Andy Lines, a Daily Mirror reporter, shared one video on Twitter that showed the expanse of the double rainbow.

Rainbow at Buckingham Palace. pic.twitter.com/qHNJMcj5UH

Photographers documenting the scene outside the palace captured images of some onlookers taking photos of the rainbows while others stood and absorbed the sight.

Queen Elizabeth II, the world's longest reigning monarch, has died.

The Royal Family announced on Twitter that the Queen "died peacefully" at Balmoral Castle Thursday afternoon.

"The King and The Queen Consort will remain at Balmoral this evening and will return to London tomorrow," the family said.

The Queen died peacefully at Balmoral this afternoon. The King and The Queen Consort will remain at Balmoral this evening and will return to London tomorrow. pic.twitter.com/VfxpXro22W

The Queen, born in 1926, was 96 year's old. She recently celebrated her Platinum Jubilee earlier this year, marking 70 years of service to the people of the United Kingdom and the Commonwealth.

She began her reign in 1952 after the death of her father, King Edward VIII.

The Queen leaves behind four children, including the heir-to-the-throne Prince Charles, Princess Anne, Prince Edward and Prince Andrew. She is also survived by her eight grandchildren, including Prince William and Prince Harry, and 12 great-grandchildren.

Her husband, Prince Philip, the Duke of Edinburgh, died last year.

During her reign, she met with 15 Prime Ministers, including her first, Winston Churchill. There have also been 14 U.S. presidents during her time on the throne, from Harry Truman to Joe Biden.

Meghan Markle, the Duchess of Sussex, will not travel to Balmoral Castle, according to the BBC.

Her husband, Prince Harry, the Duke of Sussex, is traveling to Scotland alone, a spokesperson for the couple said. He will be with his grandmother, Queen Elizabeth II, and other senior members of the Royal family soon.

Harry's brother, Prince William, and the Queen's children have already arrived in Scotland to be by the Queen's side amid growing health concerns.

Harry and Meghan were already in the United Kingdom and were due to attend the WellChild Awards this evening. Meghan will remain in London but is no longer expected to attend the event celebrating the charity of which Harry is a patron. The couple was also recently in Germany for the kickoff of the Invictus Games.

There is no word on whether she will join Prince Harry and the Royal Family at a later time.

An amendment. It is just Prince Harry travelling to Scotland. Meghan is staying in London but will not attend @WellChild this evening as has been scheduled. https://t.co/epifRP4SlZ

U.S. President Joe Biden has been briefed on Queen Elizabeth's health conditions.

"The president has been briefed and will be updated throughout the day on the concerning news out of the United Kingdom about Queen Elizabeth's health," White House Press Secretary Karine Jean-Pierre said during a press briefing Thursday.

The White House said Biden will continue to be briefed throughout the day.

"His and the first lady's thoughts are with the queen and her family today," Jean-Pierre said.

Biden also spoke with U.K. Prime Minister Liz Truss on a previously-scheduled call with allies and partners about the situation in Ukraine.

White House National Security Council Coordinator John Kirby told reporters that Biden conveyed that he and his wife, Jill Biden, are "thinking very much about the Queen and the family and the people of the United Kingdom."

Crowds could be seen gathering outside Buckingham Palace on Thursday as people waited for an update on Queen Elizabeth II following news that she was under medical supervision.

Photographers in the area captured images of people as they gathered on what was a rainy day in London.

Many of the people who gathered were seen huddling beneath umbrellas, some of which pictured the British Union Jack.

Others gathered further away from the palace gates near the Queen Victoria Memorial.

The Queen's Guard could be seen standing inside the palace gates. A sign briefly placed outside Buckingham Palace on Thursday said there would be no Changing of the Guard ceremony.

Several members of The Royal Family traveled to Balmoral Castle in Aberdeen, Scotland, on Thursday to visit Queen Elizabeth II. She is under medical supervision.

Prince William, Duke of Cambridge, was seen driving while Prince Andrew, Duke of York, sat beside him in the passenger seat. Behind them sat Sophie, Countess of Wessex and Edward, Earl of Wessex.

Amid growing concerns over the health of Queen Elizabeth II, many people are recalling her last public appearance with newly-appointed British Prime Minister Liz Truss.

The Queen met with Truss Tuesday to appoint her as Prime Minister, the 15th during her reign.

During a photoshoot at Balmoral Castle, the Queen appeared in good spirits. There was, however, a prominent bruise on her right hand.

Broadcaster Amanda Ferguson followed up in a post that speculated it may have been caused by a medial drip known as a cannula, when these are removed, bruising often occurs around the affected area.

The Queen seems to have a bruise on her right hand? Maybe from a drip?

The Queen also canceled a virtual meeting with her senior governmental advisers on the Privy Council Wednesday.

This, just days before Buckingham Palace announced Thursday that the Queen's doctor's are "concerned" about her health and placed her under medical supervision.

The BBC suspended its planned programming schedule on Thursday to pivot to live coverage surrounding Queen Elizabeth II's health.

The change was set to remain in effect until 6 p.m. local time, when regularly scheduled news programming is to resume.

This kind of live programming change has occurred in the past during developing and high-profile news events, such as the death of Prince Philip, Duke of Edinburgh, last year.

As the BBC reported on developments with The Royal Family on Thursday, presenter Huw Edwards appeared on air wearing a black suit jacket and a black tie, an apparent nod to the serious concern surrounding the queen's well-being. The network's sign language interpreters were also dressed in black while appearing on screen.

Prince Charles is now reportedly by his mother's side at Balmoral Castle in Scotland amid the Queen's concerning health.

Charles, Queen Elizabeth II's oldest child, is the heir to the throne at 73 years old. His wife, Camilla, and his sister, Princess Anne, the Princess Royal, are also with the Queen, BBC reports.

Prince Charles and the Duchess of Cornwall were seen leaving Dumfries House for Balmoral Castle to be by the Queen's side, as doctors became concerned for her health. Latest: https://t.co/8AFWhoW82a pic.twitter.com/qeK5pTGTnD

The Queen's other children, Prince Edward, the Earl of Wessex, and Prince Andrew, the Duke of York, are also on their way to Scotland.

A plane carrying seven members of the Royal family recently landed at Aberdeen Airport, the BBC reports. The airport is about an hour away from Balmoral Castle.

The plane was reportedly carried Prince William, Prince Edward, his wife Sophie and Prince Andrew.

Prince Harry and Meghan Markle are in the United Kingdom and are reportedly also heading to Scotland.

Prince Edward, Sophie Wessex, Prince William and Prince Andrew arrive at Aberdeen Airport on way to be with the Queen at Balmoral. pic.twitter.com/N7MRc95TMy

While Prince William arrives in Scotland to be with his grandmother Queen Elizabeth II, his wife and children stay behind.

Kate, the Duchess of Cambridge, will remain in Windsor with her three children, Prince George, Princess Charlotte and Prince Louis, as they start at their new school.

Today is Louis', age 4, first day at school. George, age 9, and Charlotte, age 7, previously attended the central London-based Thomas' Battersea school a short distance from the family's Kensington Palace apartment.

The family attended a "settling in afternoon" at the new school in Windsor Wednesday, Kensington Palace said.

"Ahead of their first day at Lambrook School, Prince George, Princess Charlotte and Prince Louis, accompanied by The Duke and Duchess of Cambridge, today attended a settling in afternoon for new pupils at the school," a statement released from Kensington Palace on Wednesday said. "The settling in afternoon is an annual event held to welcome new starters and their families to Lambrook and takes place the day before the start of the new school term."

The traditional Changing of the Guard ceremony was canceled at Buckingham Palace amid reports of Queen Elizabeth's health.

A sign reading "No guard changing ceremony today" was placed outside of the palace Thursday afternoon where the iconic drills take place.

However, officials have since removed the sign, according to the BBC.

Newly appointed U.K. Prime Minister Liz Truss shared her concern for Queen Elizabeth's health.

"The whole country will be deeply concerned by the news from Buckingham Palace this lunchtime," she said in a tweet. "My thoughts - and the thoughts of people across our United Kingdom - are with Her Majesty The Queen and her family at this time."

The whole country will be deeply concerned by the news from Buckingham Palace this lunchtime. My thoughts - and the thoughts of people across our United Kingdom - are with Her Majesty The Queen and her family at this time.

Truss, the new leader of the Conservative Party and former Foreign Secretary, met with the Queen at Balmoral Castle in Scotland Tuesday to formally ask her form a new government, as per tradition.

Her predecessor, Boris Johnson, submitted his resignation to the Queen in July.

This was the Queen's first in-person engagement since July. The Monarch's health concerns last week prevented her from traveling back to Buckingham Palace. This was the first time during the Queen's reign that a handover of power took place at Balmoral, instead of Buckingham Palace in London.

Members of the British royal family are rushing to be at the Queen's side Thursday after the monarch was placed under medical supervision.

Her son, Prince Charles, and his wife Camilla have reportedly already arrived at Balmoral Castle in Scotland. Her grandson, Prince William, is also on his way, CBC reported.

BREAKING: Prince Charles has arrived at Balmoral to be with the Queen. Prince William reported to be travelling to her side.

The Queen's other children, Prince Edward, the Earl of Wessex, Prince Andrew, the Duke of York, and Princess Anne, the Princess Royal, are also traveling to Balmoral.

Catherine, the Duchess of Cambridge, has reportedly remained in Windsor to be with her children, Prince George, Princess Charlotte and Prince Louis, on their first day at their new school, according to Kensington Palace.

#Update per @BBCNews: The Duchess of Cambridge has remained in Windsor as Prince George, Princess Charlotte and Prince Louis are on their first full day at their new school, Kensington Palace has said.#QueenElizabeth

Harry and Meghan, the Duke and Duchess of Sussex, are also reportedly traveling to Balmoral to be with the Queen, according to CBC.

Queen Elizabeth II has been put under medical supervision, according the Buckingham Palace.

The Queen's doctors are "concerned for Her Majesty's health" after further evaluation this morning and recommend she remain under medical supervision, Buckingham Palace said in a statement Thursday morning.

Buckingham Palace said the Queen "remains comfortable" at Balmoral Castle in Scotland.

A statement from Buckingham Palace:https://t.co/2x2oD289nL

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