Outlining his plans at Farnborough Air Show, Branson said he and his son Sam and daughter Holly hoped to make the journey on the SpaceShipTwo (SS2) aircraft by the end of 2013.

The WhiteKnightTwo aircraft that will help launch SS2 into space will also be used for a new launch vehicle, LauncherOne, which will take small satellites into space for around a tenth of the present cost, Branson said.

"Next year Holly and Sam will be joining me for a first voyage into space," he told a press conference at the show southwest of London.

"Going into space is a hard business. It keeps my mind buzzing."

Around 120 people have already signed up to make the 60-mile, two-hour journey into space -- at a cost of £128,000 ($200,000, 162,000 euros) each.

Branson added: "Virgin Galactic's goal is to revolutionise the way we get to space."

LauncherOne is expected to begin operations in 2016 and can carry up to 227 kilos (500 pounds) of weight.