The carrier vehicle will ferry suborbital craft SpaceShipTwo, modeled after Ansari X Prize winner SpaceShipOne, 50, 000 feet in the sky before releasing it.

CNN: Opening the space frontier, one tourist at a time

The Moscow talks coincided with the deployment of a Soyuz craft to ferry a new crew to the ISS. The existing crew - two Americans and a Russian - had a dramatic re-entry that took their craft more than 400 kilometres (250 miles) beyond its intended landing site.

BBC: Mars rover (Nasa)