King honours 'darling mama' on centenary of birth

King Charles III has paid a tender tribute to his late mother Queen Elizabeth on what would have been her 100th birthday, saying his "darling mama" would "remain forever in our hearts and prayers".

Elizabeth II, Britain's longest-reigning and longest-lived monarch, was born on April 21 in 1926, and spent 70 years on the throne before her death in September 2022 at the age of 96.

In a televised statement on Tuesday, Charles said his mother had shaped the world around her, and touched the lives of countless people.

"Today, as we mark what would have been my beloved mother's 100th birthday, my family and I pause to reflect on the life and loss of a sovereign who meant so much to us all, and to celebrate anew the many blessings of her memory.

"Millions will remember her for moments of national significance; many others for a fleeting personal encounter, a smile, a kind word that lifted spirits, or for that marvellous twinkle of the eye when sharing a marmalade sandwich with Paddington Bear in the final months of her life."

Elizabeth was not expected to become Queen when she was born, but after her uncle Edward VIII abdicated to marry American divorcee Wallis Simpson, her father became King George VI when she was 10.

She then became Queen herself in 1952, aged just 25.

To mark the centenary of her birth, the royal family are carrying out a number of engagements this week. On Monday, Charles and his wife Queen Camilla visited a new exhibition dedicated to her fashion, "Queen Elizabeth II: Her Life in Style", at Buckingham Palace.

On Tuesday, the King and other royals will visit the British Museum to view the final designs for a national memorial to Elizabeth in London's St James's Park, featuring statues of the Queen and her late husband Prince Philip.

"The nation will commemorate her extraordinary reign with a memorial that offers a place of reflection for generations to come," Prime Minister Sir Keir Starmer said in a statement.

The royals' commemorations come after the government announced on Sunday that a new independent charity, the Queen Elizabeth Trust, was being launched to focus on restoring shared spaces in communities, backed by £40 million ($NZ91 million) with the King as its patron.

Charles' sister Princess Anne, the Princess Royal, will officially open the Queen Elizabeth II Garden in London's Regent’s Park and the King will host a reception at Buckingham Palace in the evening.

"Much about the times we now live in, I suspect, may have troubled her deeply, but I take heart from her belief that goodness will always prevail and that a brighter dawn is never far from the horizon," Charles said.

"God bless you, darling mama. You remain forever in our hearts and prayers."