THE FLAG at Buckingham Palace was lowered to half mast at 6.30pm.
The official plans for her death, codenamed London Bridge, will now be activated.
The nation and other countries of which she was head of state will enter a 10-day period of mourning.
Details of her state funeral, accorded to monarchs, will be announced in due course, after being officially signed off by The King.
The framed formal announcement of The Queens death was affixed to the railings at Buckingham Palace at 6:45pm.
Tributes have been coming in from political leaders, past and present.
The prime minister, Liz Truss, has said the Queen’s death is a “huge shock to the nation and the world”.
Truss said, in a short speech outside Number Ten, that the Queen was “the rock on which modern Britain was built and our country has flourished under her reign”.
Truss added the Queen championed the development of the Commonwealth and “we are now a modern, thriving dynamic nation”.
Sir Keir Starmer, leader of the Labour party, said: “Today, we mourn the passing of a remarkable sovereign.
“It is a deep, private loss for the Royal Family and all our thoughts are with them at this time. The nation shares in their grief.
“We will always treasure Queen Elizabeth II’s life of service and devotion to our nation and the Commonwealth; 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. 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.
“For 70 years, Queen Elizabeth II stood as the head of our country. But, in spirit, she stood amongst us.”
Sir Tony Blair, the UK prime minister between 1997 and 2007, 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.”
Sir John Major, another former prime minister, said: “For 70 years Her Majesty The Queen devoted her life to the service of our nation and its wellbeing.
“In her public duties she was selfless and wise, with a wonderful generosity of spirit. That is how she lived – and how she led.
“For millions of people – across the Commonwealth and the wider world – she embodied the heart and soul of our nation, and was admired and respected around the globe.
“At this moment of deep sadness, I believe we all stand hand in hand with the royal family as they grieve the loss of one so loved.
“For we have all lost someone very precious to us and, as we mourn, we should be grateful that we were blessed with such an example of duty and leadership for so very many years.”
The Russian president, Vladimir Putin, has sent his condolences to Britain after the “irreparable loss” of Queen Elizabeth II.
The president of the Irish Republic, Michael D Higgins, expressed his “profound regret and a deep personal sadness” at the Queen’s death.
“Her Majesty served the British people with exceptional dignity. Her personal commitment to her role and extraordinary sense of duty were the hallmarks of her period as Queen, which will hold a unique place in British history.”
The Dutch prime minister, Mark Rutte, said the Netherlands remember the Queen “with the deepest respect”.
“During her especially long reign, she was a beacon of calm and stability for her country and the world, even at moments of the greatest historical upheaval… Today our thoughts are first and foremost with her children and grandchildren.”
The prime minister of Finland, Sanna Marin, sent her “deepest condolences to the royal family, people of the United Kingdom and the Commonwealth”.
President of the United Arab Emirates, Sheikh Mohamed bin Zayed, called the Queen “a close friend”.
“I extend my sincere condolences to the family of Queen Elizabeth II and the people of the UK,” he said.
Tributes from public figures in Wales. We will add to these as we receive them.
MARK O’TOOLE, ARCHBISHOP OF CARDIFF AND BISHOP OF MINERVIA
We have all been deeply moved to hear of the death of Her Majesty Queen Elizabeth. I ask all Catholics to pray for her, that she may hear those words from her King and Lord, ‘Well done, good and faithful servant – enter into the rest of your Master.’ We pray too for King Charles and all the Royal Family, that they may be comforted at this time of loss.
I was giving a talk this evening in the Vatican to catechists, bishops and priests from across the world on what it means to try and pass on the Christian Faith. I paused my talk at about 6.20pm UK time for a moment of silence, so that we could recall Queen Elizabeth’s exceptional Christian witness and the way she so often spoke of her relationship with Jesus Christ. All 1,000 of us in the Audience Hall of Paul VI prayed for the Queen at that poignant moment. Shortly afterwards we all heard the news she had died a few hours before.
We entrust her soul to the mercies and blessings of the Lord.
PLAID LEADER ADAM PRICE
Her Majesty the Queen’s long reign saw a period of immense change for Wales, the United Kingdom and the rest of the world.
Her deeply held sense of duty was recognised by millions across the globe, and many will remember her as a figure which provided comfort, stability and continuity during times of crisis.
On behalf of Plaid Cymru, I extend our deepest condolences to the Royal Family at this difficult time.
PEMBROKESHIRE COUNTY COUNCIL CHAIRMAN, CLLR. PAT DAVIES
I would like to pass on my condolences, those of the entire Council and the people of Pembrokeshire to The Royal Family on this saddest of days.
We have always known this day would come but it does not make it any less painful.
For millions of people, as our longest reigning monarch, Her Majesty has been a constant and reassuring figure in our lives.
We are thankful for her many decades of public service and the example she set.
SAM KURTZ MS
A life of dedicated, dutiful service to our nation and the Commonwealth.
Her Majesty was the strength and stay of our nation during her 70-year reign. She was a mother to her family and to our country.
I will remember her with profound respect and admiration.
Together, we mourn the sad death of Her Majesty Queen Elizabeth II.
My deepest condolences to the Royal Family at this sad time. May she rest in peace.
THE FIRST MINISTER, MARK DRAKEFORD MS
Incredibly sad to hear of the passing of HM Queen Elizabeth II. As our longest reigning monarch, she firmly upheld the values and traditions of the British Monarchy. On behalf of the people of Wales I offer our deepest condolences to Her Majesty’s family during this sad time.
JONATHAN EDWARDS MP
Her Majesty the Queen dedicated her life to public service making an unrivaled contribution which is recognised all over the world.
Ultimately our thoughts will be with her children and grandchildren as they grieve at the loss of the head of their family.
ELUNED MORGAN MS
Thank you for selfless service and reassuring presence throughout decades of change. You will be sorely missed Ma’am.
PAUL DAVIES MS
I am deeply saddened to hear of the passing of HM Queen Elizabeth II.
A remarkable woman, who served us all with dedication and devotion.
My sincerest condolences to the Royal family at this very sad time.
CHARLIE EVANS, CHAIR, CWSP CONSERVATIVES
Well done good and faithful servant
Our beloved HM The Queen now sees her Saviour face to face.
God bless her. God bless her family. God save the King.
STEPHEN CRABB MP
I am deeply saddened to learn of the passing of Her Majesty Queen Elizabeth II.
The nation mourns a remarkable Sovereign who served the United Kingdom and Commonwealth with the greatest devotion, strength and selflessness for more than 70 years. In times of national trial and hardship she never faltered, instead rising to the occasion to provide the country with stability and reassurance.
I offer my deepest condolences to the Royal Family at this incredibly sad time.
Rest in Peace HM Queen Elizabeth II.
NFU CYMRU PRESIDENT, ALED JONES
There is a deep feeling of melancholy amongst the Welsh farming community following news of the passing of Her Majesty the Queen.
Her Majesty was a symbol of dedication and commitment to public service, she has been a stoic servant to the country for an extraordinary seven decades, a remarkable reign at the throne of our monarchy.
The Queen’s warm affiliation with the Great British countryside is well documented and that connection has been valued and appreciated by the nation’s farmers.
On behalf of farmers across Wales, I send my deepest condolences to the Royal Family at this very sad time and offer my heartfelt best wishes at this time of national mourning.
WELSH LIBERAL DEMOCRAT LEADER JANE DODDS
I am deeply saddened to hear of the death of Her Majesty Queen Elizabeth II. My thoughts are with the King, her majesty’s other children, grandchildren and all those close to her at this difficult time.
Her Majesty’s passing, without a doubt, does mark the end of a very long, and indeed a seminal chapter in the history of our nations and for most people her presence has been one of the few constants throughout their lives.
Throughout her life, Her Majesty served the country with the absolute greatest dedication, honour and dignity. From serving in the Auxiliary Territorial Service during World War Two, to taking the time to speak to local schoolchildren at the opening of the Senedd last year, she never once shied away from public duty.
Her life will forever be interlinked with that of a period of great change within the UK and although many today would struggle to recognise the world she had been born into, she always seemed to belong very much here today in the present.
Her Majesty was always a great friend to Wales and she will be deeply missed within the UK, the Commonwealth and further afield. I pray that her journey into the next stage has been peaceful and that she is at rest.