King Charles turns 76 after year of little celebration

Britain's head of state King Charles III turned 76 on Thursday, after a torrid year in which both he and his daughter-in-law Catherine, Princess of Wales, have battled cancer.

Ceremonial gunfire rang out across the British capital to mark the occasion after Charles spent the morning visiting a surplus food distribution centre in south London.

His wife, Queen Camilla, 77, did not join him at the Coronation Food Hub in Deptford as she was recovering from a chest infection that prevented her from attending last weekend's Remembrance events for Britain's war dead.

Senior royals wished him happy birthday with William, his elder son and heir, sharing a photo online of his father wearing sunglasses and a floral garland.

William has described the last 12 months as a "brutal" year because of the health issues affecting his wife and father that forced both to step back from royal duties.

The king's cancer diagnosis was announced in February but two and a half months at the end of April he was back at work.

"The problem is trying to stop him," Camilla has said several times since.

Last month, the couple visited Australia then Samoa for a Commonwealth heads of government meeting. Charles paused his cancer treatment during the trip.

According to those close to him, Charles returned "invigorated" from the 11-day trip, while one palace official said the king intended to return to a "normal" schedule of overseas trips next year.

His desire to fulfil his public duties may be influenced by the fact when he succeeded his mother Queen Elizabeth II, he was the longest-serving heir apparent in British history at 70 years.

Upon ascending the throne on September 8, 2022 when Elizabeth died, Charles pledged to perform his constitutional role "throughout the remaining time God grants me".

Last Sunday, he led the nation in a two-minute silence to honour Britons killed in battle since 1914 at the Cenotaph memorial in London, one of the most important dates in the royal calendar.

The previous evening, he joined William and Kate, as Catherine is widely known, who recently completed chemotherapy for her own cancer diagnosis this year -- at the Royal Albert Hall for a commemorative concert.

On Tuesday he hosted the king of Bahrain, then on Wednesday held a reception at Buckingham Palace for the British film and TV industry, before attending a screening of "Gladiator II" to mark its global release.

Members of the public on Thursday greeted him at the Coronation Food Hub, a project he launched on his 75th birthday last year to tackle food waste and support people in need.

Charles's late mother remains at the top of YouGov's royal popularity rankings, followed by Kate, his sister Princess Anne, and William. Charles is at fifth place.