King Charles pays tribute to his ‘beloved mother’

The new king has paid tribute to his "beloved mother" in a statement declaring the death of the Queen to be "a moment of the greatest sadness for me and all members of my family".

The first statement "from His Majesty the King" 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."

In remarks released just half an hour after Buckingham Palace announced that the Queen, 96, had died peacefully at Balmoral on Thursday afternoon, Charles, 73, said: "During this period of mourning and change, 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."

The statement was issued with a Buckingham Palace letterhead, a further sign of the former Prince of Wales's transition to head of state after some seven decades as heir to the throne.

Minutes later speaking from Downing Street, the prime minister, Liz Truss, described the new monarch as King Charles III, confirming that is how he will be known, ending speculation he may choose a different name under which to reign. She described the Queen as the "rock on which modern Britain was built" and ended her statement with the words: "God save the King."

King Charles III, and his wife Camilla, who is expected to be known as Queen Consort after an edict from the Queen during her platinum jubilee, are expected to remain at Balmoral on Thursday night and will return to London on Friday. The King's new responsibilities will begin with leading the nation in mourning for its longest serving monarch.

Also at Balmoral on Thursday evening were the Duke of York (who remains stripped of royal duties over his links to convicted sex offender Jeffrey Epstein), and the Earl and Countess of Wessex, who flew to Aberdeen from London on the same RAF plane as the Duke of Cambridge. The jet touched down in Aberdeen just before 4pm. They were joined at Balmoral by the Queen's only daughter, Princess Anne.

The new King and Queen Consort had been carrying out engagements in Scotland in recent days and Charles was said to have been making regular morning visits to see his mother as she continued to struggle with her mobility.

The Duke and Duchess of Sussex, who happened to be in the UK, had been due to attend the WellChild Awards ceremony in London on Thursday evening but Harry travelled to Balmoral and was expected to arrive on Thursday evening.

Prince William, now heir to the throne, has immediately inherited the title the Duke of Cornwall and is now the Duke of Cornwall and Cambridge, with Kate now the Duchess of Cornwall and Cambridge, and their children also becoming "of Cornwall and Cambridge". By convention he is likely to become Prince of Wales but that is a title in the gift of the new King. George, their eldest child, is now second in line to the throne, Charlotte third, and Louis fourth, with Harry once again fifth in line. Kate is now a queen in waiting.

Sources familiar with Charles cited his "deep emotional facility for helping people around loss" and expected him to prove a strong support as his family and the nation grieves.

Charles' reign will begin with visits to all the home nations and playing a central role in the carefully choreographed events around which national mourning will be structured in the coming days leading up to the Queen's state funeral at Westminster Abbey, likely to be on 19 September.

"He will be focused on the personal and the family, but for the palaces it will be a question of [choosing] the right things to say and do that lead the nation in mourning but also establish the first steps of the new reign," said a former aide.

As Prince of Wales, the King displayed a wide range of interests, which have sometimes courted controversy. These include the built environment, global sustainability, faith, medicine and rural affairs.

His interventions on policy matters in these areas through in so-called "black spider memos" scrawled to government ministers have led to warnings from constitutional experts that he will need to change his approach to potentially contentious areas as King.

His leading youth charity, the Prince's Trust, helps disadvantaged and vulnerable young people, using practical support including training, mentoring and financial assistance, and is seen as one of his greatest successes.

He has described how he wanted to make the most of his position within the royal family.

"I've had this extraordinary feeling, for years and years, ever since I can remember really, of wanting to heal and make things better," he told the US's Time magazine. "I feel more than anything else it's my duty to worry about everybody and their lives in this country, to try and find a way of improving things if I possibly can."

In 2014, one courtier who has known Charles for many years asked by the Guardian to suggest what kind of king he would be, said: "He will be true to his beliefs in his contributions. Rather than a complete reinvention to become a monarch in the mould of his mother, the strategy will be to try and continue with his heartfelt interventions, albeit checking each for tone and content to ensure it does not damage the monarchy."