The Prince and Princess of Wales have written an emotional tribute to the late Queen Elizabeth II on what would have been her 100th birthday. Prince William and Kate posted a beautiful photo of the former monarch, including one of her as a young woman.

In a beautifully crafted message the royal couple wrote: “Remembering Her Majesty Queen Elizabeth II on the 100th anniversary of her birth. Inspiring generations through a lifetime of duty.”

He acknowledged the many challenges and issues nationally and across the globe that may have caused her reason for concern, and renewed his “own solemn pledge of duty and service to you all”.

Later today, the King will also attend a Buckingham Palace reception with charities and organisations associated with the late Queen invited, including Cancer Research UK, the Jockey Club and the Army Benevolent Fund.

Guests will include some of the UK’s oldest citizens celebrating their 100th birthday on April 21, with the King presenting their centenary cards in person.

The late Queen’s only daughter, Princess Anne, was also opening a memorial garden in her mother’s name in Regent’s Park in London this lunchtime on the 100th anniversary of her birth.

Members of the monarchy visited the British Museum today to see a scale model of the Queen Elizabeth Memorial with architect Lord Foster, who won the bid to design a national monument in tribute to her.

The final masterplan for the central London tribute has been unveiled to coincide with what would have been the late Queen’s 100th birthday.

The late Queen would have turned 100 today and the King said her existence should be celebrated as a “life well-lived” rather than marking an “absence” ahead of a series of royal events.