King Charles III portrait released to mark 74th birthday

The monarch has also officially become Ranger of Windsor Great Park

A new portrait of King Charles III has been released to coincide with his birthday.

The photograph shows the King, who turns 74 today, leaning against an ancient oak tree in Windsor.

Buckingham Palace has announced that the King has officially become Ranger of Windsor Great Park, 70 years after his father the Duke of Edinburgh was appointed to the post.

The role of Ranger offers oversight and guidance to the deputy ranger and his team in the day-to-day stewardship of one of the country's oldest landed estates.

Paul Sedgwick, The Crown Estate's managing director, rural and deputy ranger of Windsor Great Park, said: “We are honoured to have His Majesty as Ranger of Windsor Great Park, continuing a long tradition of the Sovereign and members of the Royal Family holding this role.

“Windsor has a wonderful heritage with many precious natural habitats.

“His Majesty's passion and commitment to the natural world will be invaluable as we seek to become a centre of excellence for environmental best practice, preserving and enhancing the Great Park for generations to come.”

The King will be spending his birthday privately, with no official engagements planned.

Military celebrations are marking the day, with the Band of the Household Cavalry playing “Happy Birthday” outside Buckingham Palace during the changing of the guard ceremony.

Gun salutes are also being fired across London, with the King's Troop Royal Horse Artillery firing 41 rounds from Green Park.

An hour later, the Honourable Artillery Company will fire a 62-gun salute from the Tower of London.

During a tour of Yorkshire last week, the King appeared to be impressed after being presented with an early birthday card.

Leeds’s 10-year-old mayor Mason Hicks presented the monarch with the card.

“Thank you - you’re very clever to know it’s my birthday,” the King said.

Without missing a beat, the youngster replied that it’s “next Monday,” to which his Majesty replied: “I know! Just under a week.”