Prince William plans boating bachelor party

Britain's Prince William will have his bachelor party at sea.

The second-in-line to the British throne - who will marry long-term girlfriend Kate Middleton on April 29 - will celebrate his last days of being a single man with a day of watersports alongside his best man, younger brother Prince Harry, and 20 of his closest pals.

A royal source told The Sun newspaper: "The watersports weekend is a perfect option. They can let their hair down without worrying about who is around."

Harry, 26, has then planned for his 28-year-old brother and their friends to end the day with a barbeque and a trip up a nearby estuary to visit a number of pubs and restaurants only accessible by boat.

He has reportedly chosen a firm based on the south coast of Britain, with the whole event not expected to exceed £2,500.

The group are expected to stay at a nearby country house belonging to a friend.

Both William and his future bride Kate, 29, were advised by their royal security team - who need to monitor the couple - to have their bachelor and bachelorette parties in Britain.

The couple have also made it known they don't want lavish trips abroad while the country is in recovery from recession.