A privately-built manned spaceship has touched down in California's Mojave Desert after a flight that sponsors say was high enough to claim a $10 million prize.

Preliminary radar readings show that SpaceShipOne reached a peak altitude of more than 114 kilometers.

If that height is confirmed, the ship's sponsors will be awarded the $10 million Ansari X prize, created to promote commercial space travel.

To win the money, a privately-developed spacecraft able to carry three people must fly at least 100 kilometers above the Earth twice within two weeks.

Last Wednesday, SpaceShipOne reached a height of 103 kilometers.

Virgin Group financier Richard Branson has announced plans to offer commercial space flights to civilians beginning in 2007.

Some information for this report provided by AP, AFP.