The UK's most senior political figures have expressed their condolences following the death of the Queen on Thursday afternoon aged 96.
In a statement made at 6.30pm, Buckingham Palace 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."
Her son, now King Charles III, has become her successor.
It came after senior members of the Royal Family rushed to Balmoral in Scotland after the Palace announced her doctors were "concerned for Her Majesty’s health".
Condolences have poured in from politicians from across the political spectrum following her death.
Prime minister Liz Truss, who was appointed to the role just two days ago by the Queen, said she was "the rock on which modern Britain was built".
"In the difficult days ahead, we will come together with our friends across the United Kingdom, the Commonwealth and the world to celebrate her extraordinary lifetime of service."
Labour leader Keir Starmer said the Queen was "our longest-serving and greatest monarch".
"Above the clashes of politics, she stood not for what the nation fought over, but what it agreed upon," he said.
"As Britain changed rapidly around her, this dedication became the still point of our turning world.
"So as our great Elizabethan era comes to an end, we will honour the late Queen's memory by keeping alive the values of public service she embodied."
Scottish National Party (SNP) leader Ian Blackford said his "thoughts, prayers and deepest condolences" were with the Royal Family.
"The Queen was a constant figurehead throughout our lives, and she showed an inspiring commitment to the values of leadership, duty and service throughout her long reign," he said.
"In the period ahead, there will be time to reflect on the incomparable legacy and impact that the Queen had on these islands, our history and world events."
Liberal Democrats leader Ed Davey said the Queen served the country "faithfully all her life".
"The Queen was an ever-fixed mark in our lives," he said. "She represented duty and courage, warmth and compassion."
Leaders of devolved administrations across the UK also expressed their sadness.
Scotland's first minister Nicola Sturgeon said her passing was a "profoundly sad moment for the UK, the Commonwealth and the world".
Sturgeon said the Queen's life "was one of extraordinary dedication and service", and sent her condolences to the king on behalf of Scotland.
Welsh first minister Mark Drakeford said the Queen "firmly upheld the values and traditions of the British monarchy".
"We pay tribute to Her Majesty's dedication and selfless devotion," he said. "She will be sorely missed by the many organisations for which she was a patron and president."
Former prime ministers also publicly expressed their sorrow.
Tony Blair said: "We have lost not just our monarch but the matriarch of our nation, the figure who more than any other brought our country together, kept us in touch with our better nature, personified everything which makes us proud to be British."
Boris Johnson said it was the nation's "saddest day", and that the Queen had "modernised the constitutional monarchy".
"Though our voices may still be choked with sadness, we can say with confidence the words not heard in this country for more than seven decades: God save the King."
Gordon Brown said "the entire world are joined together in mourning".
He added: "HM Queen Elizabeth II served this country to the last. I offer my sincere condolences to the Royal Family. May she rest in peace."
Theresa May said it was the "honour of [her] life to serve as her prime minister", and said the Queen "devoted herself unreservedly to a life of service".
The Queen was the longest-reigning British monarch in history, celebrating her Platinum Jubilee in 2022 after 70 years on the throne.
Crowds broke out into the national anthem outside Buckingham Palace following the announcement of her death, with many weeping after the flag was lowered to half mast.
Her son, King Charles, said it was "a moment of greatest sadness for me and all members of my family".
"We mourn profoundly the passing of a cherished sovereign and 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."
In a speech to mark her 21st birthday in 1947, the Queen vowed to dedicate her life to the service of the Commonwealth.
"I declare before you all that my whole life, whether it be long or short, shall be devoted to your service and the service of our great imperial family to which we all belong."