Europe and the US could be building a spaceship together later this decade.
It is one of the ideas being considered as Europe ponders the next evolution of its ATV orbital freighter.
The sophisticated robotic vessel is used to transport up to 7.5 tonnes of supplies to the space station, but only three more units are in production.
Europe is now looking to develop a derivative of the ship and a joint venture with the Americans on a future vessel is being discussed.
The European Space Agency's Director General, Jean-Jacques Dordain, said the new concept must leverage the capabilities of the existing vehicle, such as its automatic rendezvous and docking technology, but that its precise role was up for debate.
