Her Majesty, Queen Elizabeth II, has died aged 96 at her Scottish country residence, Balmoral.
She served as the Queen of the United Kingdom and of the Commonwealth for 70 years, having come to the throne at the age of just 25.
She was born in 1926.
Clarence House has said Prince Charles and Camilla, as well as Prince William, are at Balmoral.rea
A fleet of cars believed to be carrying the Duke of Cambridge, Duke of York and the Earl and Countess of Wessex arrived at Balmoral just after 5pm.
The plane carrying the royal party had arrived at Aberdeen Airport just before 4pm.
Flowers outside Buckingham Palace
People have begun laying flowers at the gates of Buckingham Palace as news spreads that the Queen is under medical supervision.
A woman laid the first bouquet at the Queen’s central London residence just after 5pm.
The crowd outside Buckingham Palace has swelled to a few hundred.
A downpour which drenched those waiting at the gates has abated, leaving a hushed silence among those gathered.
People among the hundreds-strong crowd outside the Buckingham Palace gates turned round to take pictures of a rainbow that appeared after a heavy downpour.
The head of state pulled out of a virtual Privy Council on Wednesday after doctors ordered her to rest.
The Duchess of Cornwall had been scheduled to open a new visitor centre for the Great Tapestry of Scotland in Galashiels, in the Scottish Borders, on Friday.
However, a royal spokesperson said that both she and the Prince of Wales had travelled to Balmoral, and it was “looking more likely” that the engagement would be cancelled.
The royal family’s website appears to have crashed following the news of the Queen’s health concerns.
An error message appeared on screen reading: “Gateway time-out”.
Prime Minister Liz Truss said: “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.”Prime Minister Liz Truss
Speaker Sir Lindsay Hoyle interrupted the speech of SNP Westminster leader Ian Blackford during the energy debate to tell MPs: “I know I speak on behalf of the entire House when I say that we send our best wishes to Her Majesty the Queen and that she and the royal family are in our thoughts and prayers at this moment.”
He added: “If there is anything else, we will update the House accordingly.”
Labour leader Sir Keir Starmer said he is “deeply worried” by the news from Buckingham Palace and he is hoping for the Queen’s recovery.
He tweeted: “Along with the rest of the country, I am deeply worried by the news from Buckingham Palace this afternoon.
“My thoughts are with Her Majesty the Queen and her family at this time, and I join everyone across the United Kingdom in hoping for her recovery.”
US President Joe Biden told Liz Truss he was “keeping the Queen and her family in their thoughts”, the White House said.
The president and the Prime Minister were taking part in a video conference about the war in Ukraine.
“President Biden also conveyed to Prime Minister Truss that he was following reports about Queen Elizabeth’s health and that he and the First Lady are keeping the Queen and her family in their thoughts,” a White House statement said.
Meanwhile, Scotland’s First Minister Nicola Sturgeon said: “All of us are feeling profoundly concerned at reports of Her Majesty’s health.
“My thoughts and wishes are with the Queen and all of the royal family at this time.”
Wales’ First Minister Mark Drakeford said in a tweet: “Concerned to hear the news from Buckingham Palace.
“I send my best wishes to Her Majesty and her family on behalf of the people of Wales.”
Holyrood’s Presiding Officer has said the thoughts of all in the Scottish Parliament are with the Queen after Buckingham Palace said she was under medical supervision at Balmoral.
Speaking after First Minister’s Questions, Alison Johnstone made a brief statement to MSPs.
“I am aware that a statement has been made at Westminster on the health of Her Majesty the Queen,” she said.
“I will, of course, monitor developments and keep members updated over the course of the day.
“But my, I’m sure the thoughts of all in Parliament are with Her Majesty at this time.”
SNP Westminster Leader Ian Blackford said he was “saddened” to hear the announcement made about the Queen’s health.
Speaker Sir Lindsay Hoyle interrupted Mr Blackford’s speech in the energy debate to say the House sends its best wishes to the Queen.
Resuming his speech, Mr Blackford told the Commons: “I’m sure on behalf of all colleagues that we’re saddened to hear the announcement that has been made, and the thoughts and prayers of all of us will be with Her Majesty the Queen and indeed with the royal family.”
Former Conservative prime minister David Cameron said he was “deeply concerned” by the news about the Queen’s health.
“Deeply concerned by the news this afternoon from Buckingham Palace,” he tweeted.
“I send my heartfelt thoughts and prayers to Her Majesty The Queen and the Royal Family at this worrying time.”
The Archbishop of Canterbury has said the “prayers of the nation” are with the Queen.
“My prayers, and the prayers of people across the (Church of England) and the nation, are with Her Majesty The Queen today,” Justin Welby tweeted.
“May God’s presence strengthen and comfort Her Majesty, her family, and those who are caring for her at Balmoral.”