Russian space agency Rosaviakosmos has signed a contract with US firm Space Adventures, which is tasked with finding two candidates for the space flights, Rosaviakosmos spokesman Sergei Gorbunov told the ITAR-TASS news agency.

The asking price for a 10-day trip to the ISS is around 20 million dollars, a sum only two space tourists, Californian businessman Dennis Tito and South Africa Internet millionaire Mark Shuttleworth, have been prepared to pay so far.

Trips scheduled by US pop singer Lance Bass from the boy band 'N Sync and former NASA official Lori Garver was called off after they were unable to pay.

Russia and the United States, the ISS's major partners, have clashed over Moscow's keenness to raise money for its cash-strapped space programme by selling tourist tickets to the ISS.

In February, Russia announced the temporary suspension of space tourist flights after the US shuttle Columbia disentegrated on its way back to earth from the ISS. The tragedy forced the United States to rely completely on Russian craft to ferry crew and supplies to the ISS.

SPACE.WIRE