Prince Charles has taken a break from a round of parties marking his 60th birthday to promote the work of his leading charity.

At Beckton Community Centre in London, Prince Charles was presented with a birthday cake, topped with a replica of a London bus pass. To the left is the Duchess of Cornwall, his wife of three years.At Beckton Community Centre in London, Prince Charles was presented with a birthday cake, topped with a replica of a London bus pass. To the left is the Duchess of Cornwall, his wife of three years. (John Stillwell/Associated Press)

Charles attended the launch of a new project run by his Prince's Trust as he passed the milestone year on Friday.

His wife, the Duchess of Cornwall, was by his side as he visited the Beckton Community Centre in east London to launch Youth Week, a campaign to highlight the positive contributions young people can make to society.

All week, there have been celebrations for Britain's longest monarch-in-waiting.

The festivities began Wednesday with a comedy show at New Wimbledon Theatre in south London, where John Cleese, Rowan Atkinson and Robin Williams entertained Prince Charles, the Duchess of Cornwall and Prince Harry.

On Thursday a banquet was held in Charles's honour at Buckingham Palace, attended by 400 guests.

His wife, Camilla, has organized a private party for Saturday at Highgrove, the Prince's rural Gloucestershire estate, a bash that will feature a performance by Rod Stewart, himself a sexagenarian.

Charles Philip Arthur George was born on Nov. 14, 1948. He became heir apparent on the death of his grandfather King George VI in 1952 as his mother, Queen Elizabeth, took the throne when he was three years old.

There is always speculation on when Charles will become king, but the Queen, now 82, took an oath to be reign until her death. While she has informally indicated that she plans to keep the job for life, she gave her son a strong personal endorsement on Wednesday.

"For Prince Philip and me, there can be no greater pleasure or comfort than to know that into his care are safely entrusted the guiding principles of public service and duty to others," she said.

"If he never does gets to the throne, he will at least look back on the charity work and say 'I was defined by that,'" said Andrew Pierce, who covers the royals for London's Daily Telegraph.

Britain's next-longest monarch-in-waiting was Queen Victoria's eldest son, who became King Edward VII in 1901, aged just over 59 years and two months.