The royal family has wished the King a happy 76th birthday, with the Prince and Princess of Wales sharing a photo of the relaxed-looking monarch wearing sunglasses and a garland during a recent royal tour.

The monarchy’s official social media accounts posted a congratulatory message with a more formal portrait of the King standing in the White Drawing Room at Buckingham Palace.

William and Kate’s account shared an image of Charles in the sunshine during his recent long-haul overseas trip to Samoa as he was opening The King’s Garden at the Robert Louis Stevenson Museum in Apia.

The message read: “Wishing a very Happy Birthday to His Majesty The King!”

Charles is treating his birthday as a normal working day and carrying on with his duties despite facing a personally challenging year in which both he and daughter-in-law Kate were diagnosed with cancer.

The King will open the first two Coronation Food Hubs on the first anniversary of the launch of his Coronation Food Project, designed to bridge the gap between food need and food waste in the UK amid the cost-of-living crisis.

He will head to Deptford in south London to formally unveil the first hub, tour the centre with London Mayor Sadiq Khan, and attend the surplus food festival being staged to celebrate the royal visit, before virtually opening another hub in Merseyside.

The event will be a solo one for Charles, with the Queen, who had hoped to join him, still recovering from a nasty chest infection.

The King, in black tie, walked the red carpet on the eve of his birthday, meeting stars Denzel Washington, Paul Mescal and Pedro Pascal at the glitzy global premiere of Gladiator II.

The King meets Pedro Pascal whilst attending the Royal Film Performance of Gladiator II on Wednesday evening
The King met the stars of Gladiator II at its premiere on Wednesday evening (Eddie Mulholland/The Telegraph/PA)

On Wednesday afternoon, he hosted a special celebrity reception at Buckingham Palace in honour of the UK’s film and television industry, where he and Camilla, who attended for part of the event, chatted with a host of famous faces including actors Damian Lewis, Emily Mortimer and Lucien Laviscount, and Gladiator director Sir Ridley Scott.

Gun salutes will be fired in Green Park by The King’s Troop Royal Horse Artillery and at the Tower of London by the Honourable Artillery Company as part of the military’s traditional celebrations on the sovereign’s birthday, and bells will be rung at Westminster Abbey where the King was crowned in 2023.

Charles, like his late mother Elizabeth II, has two birthdays, his actual one on November 14, and his official one, which falls on the second Saturday in June.

The King and the royal family during his official birthday celebrations in June
The King and the royal family during his official birthday celebrations in June (Gareth Fuller/PA)

Since 1748, the monarch’s official birthday has been marked by the parade known as Trooping the Colour, which was usually held on the king or queen’s actual birthday.

Edward VII, who reigned from 1901 to 1910, was born in the month of November.

But he celebrated officially in May or June because there was less chance of it being cold and drizzly during the outdoor event.

Charles’s grandfather George VI, who was born in December, reintroduced the idea, and the late Queen Elizabeth II continued it, as has the King.

Princess Elizabeth gazes at her first born Prince Charles as she holds him in her arms after his christening in 1948
Charles pictured in the arms of his mother, the late Queen, after his christening in 1948 (PA)

Prince Charles Philip Arthur George was welcomed into the world on November 14, 1948 at Buckingham Palace, the first child of the future Queen Elizabeth and Prince Philip, the Duke of Edinburgh.

As the Prince of Wales, he was the nation’s longest serving heir to the throne, and he became King on September 8, 2022 on the death of his mother.

News of Charles’s cancer, undisclosed in its form, came in February, after it was discovered while he was treated in hospital for an enlarged prostate in January.

He cancelled all face-to-face public duties but returned in April and has since travelled to France for D-Day commemorations, hosted an incoming state visit for the Emperor of Japan, and undertaken a recent hectic tour to Australia and Samoa with the Queen, despite still undergoing outpatient cancer treatment.