Prince Harry appears, alone, for UK Invictus Games service

LONDON (Reuters) -Prince Harry made a rare public appearance in Britain on Wednesday when he attended a service of thanksgiving to mark the 10th anniversary of the Invictus Games, with the strained relationship with his family dominating attention.

Harry, 39, the younger son of King Charles and who now lives in California with his American wife Meghan and their two children, has become estranged from the other royals after criticising them and the institution itself in his recent memoir, interviews and TV documentaries.

Although he made a flying visit to see Charles for a quick reunion after Buckingham Palace revealed that the 75-year-old king had been diagnosed with cancer in February, the father and son will not meet up on his latest trip.

"It unfortunately will not be possible due to his majesty’s full programme," said a spokesperson for Harry, the Duke of Sussex. "The duke of course is understanding of his father's diary of commitments and various other priorities and hopes to see him soon."

While Harry was at London's St Paul's Cathedral for the Invictus Games service, the king was hosting the annual garden party at Buckingham Palace, accompanied by other senior royals. The monarch was also due to carry out an engagement at a military training base on Thursday.

It meant Harry was the only royal figure at St Paul's for the gathering to celebrate the international sporting event that he founded in 2014 for military personnel wounded in action.

Harry, who arrived alone, smiling and waving to a crowd outside gave a reading, and actor Damian Lewis recited a poem to the congregation which included veterans and wounded service personnel.

Footage from the service showed Harry greeting guests inside the cathedral, and then shaking hands and chatting briefly with some of the cheering wellwishers outside before he left.

After leaving Britain, Harry will be joined by his wife Meghan, who did not come with him to London, for a visit to Nigeria.

(Reporting by Michael Holden, editing by William James and Angus MacSwan)