Prince William says it 'feels great' to be Harry's best man

Prince William says it "feels great" to be his brother Prince Harry's best man at his wedding to Meghan Markle next month.

As the princes opened a sports centre in London, William was asked by Sky News' Royal Correspondent Rhiannon Mills how it felt to be asked to support his brother on his big day.

"It feels great, feels great," he replied, saying that he was "really delighted".

"Revenge is sweet, Rhiannon, revenge is sweet," he added, presumably referring to Harry's turn as his best man when he married Kate Middleton in 2011.

The brothers are known for being jocular with each other at times, and Harry looked somewhat affronted at the idea of revenge.

When William was then asked how Harry had asked him to be best man, Harry replied that he "got down on one knee".

Turning to the camera, the younger Royal added: "He's known for months".

William was also asked about his own pressing issue - the name of his and the Duchess' third child, a boy who arrived on Monday.

"I'm working on it," he replied.

Harry will marry Ms Markle at St George's Chapel in Windsor next month with approximately 600 guests invited to the ceremony.

Earlier, a statement from Kensington Palace said the Duke of Cambridge was "honoured to have been asked" and is "very much looking forward to supporting his brother" on 19 May.

Officially there is no such thing as a best man at a Royal wedding, which instead uses the term "supporters", but Prince Harry is known to break with tradition.

When asked about the possibility of being best man or supporter in January, William responded: "He hasn't asked me yet... so it could be a sensitive issue."

Ms Markle has made no announcement yet about her maid of honour, but some of her celebrity best friends are being touted as possible candidates.

They include Serena Williams, actress and UNICEF ambassador Priyanka Chopra and British reality TV star Millie Mackintosh.

The wedding date clashes with the FA Cup final, but it is understood that Prince William, who is president of the Football Association, will be concentrating on his duties as best man so won't be able to make it to Wembley.