While a test of SpaceXs Dragon spacecraft docking capabilities with the International Space Station is tentatively scheduled for December, 2011, Russia has said it will not allow a SpaceX vehicle to dock with the ISS unless its safety is fully tested. We will not issue docking permission unless the necessary level of reliability and safety is proven, said Alexei Krasov, head of the human spaceflight department of Roscosmos. So far we have no proof that those spacecraft duly comply with the accepted norms of spaceflight safety.
NASA has not yet commented on the statement by Krasov, which was reported by the Russian media.
SpaceX has requested NASA to authorize the docking in December after another test flight of the Dragon sometime this summer. As it stands now, approximately twelve cargo resupply flights are planned by SpaceX through 2015, and SpaceX CEO has said he would like to start crewed flights by 2016.
Some critics are viewing Russias objections as having little to do with safety and more to do with the monopoly it will have for access to the ISS once the space shuttle program concludes later this summer. Russia has raised its going rates for ferrying US astronauts to the space station on the Soyuz space craft and for bringing cargo with the Progress craft resupply ship.
Explore further: Image: Martian sand dunes in spring