A company that sends wealthy tourists into space aboard Russian rockets said Wednesday that it has a new client, Google co-founder Sergey Brin, and a new plan for the first entirely private flight to the international space station.

Space Adventures Ltd. said Brin, a native of Moscow, had paid $5 million to reserve a seat on a future flight.

Just where and when the 35-year-old billionaire might fly is still up in the air. Since 2001, the company has sent five tourists to the space station.

Space Adventures also said that it had reached an agreement to preserve its partnership with Russia. Space Adventures plans to charter an entire space flight, just for itself, with space for two clients plus a Russian cosmonaut. Russia's Federal Space Agency would still run the mission, but Space Adventures would pay for the trip and buy its own Soyuz spacecraft.