NASA and the Russian space agency Roscosmos have announced a new partnership for human exploration of the moon and deep space. The agencies have agreed to cooperate on the NASA-led Deep Space Gateway program which includes building the first lunar space station, all part of a long-term project to send humans to Mars. Both agencies signed a joint statement on September 27, at the 68th International Astronautical Congress in Adelaide, Australia.

The decision to partner with Roscosmos on human missions to the moon and beyond came about as NASA continues to expand on its Deep Space Gateway program. The concept, announced earlier this year, is a mission architecture designed to send astronauts into lunar orbit by the 2020s. The project involves building a crew-tended lunar space station in lunar orbit that would serve as a “gateway to deep space and the lunar surface,” NASA has said.

“The partners intend to develop international technical standards which will be used later, in particular to create a space station in lunar orbit,” Roscosmos said in a separate statement. The two countries would cooperate to build the systems necessary to organize scientific missions in lunar orbit and to the surface of the moon, the agency added.

A crewed mission to the moon and beyond would likely involve NASA’s new Space Launch System (SLS) rocket for deep space flights and the Orion space capsule. According to Roscosmos, the partners also discussed the possibility of using a Russian rocket to complete the construction of the orbital moon station.

“At the first stage, [the deep space gateway] is supposed to use the American super heavy SLS in parallel with the domestic heavy rockets Proton-M and Angara-A5M,” Roscosmos officials said. “After the creation of the Russian super heavy rocket, it will also be used [for] the lunar orbital station.”

Although the plan challenges the current capabilities in human spaceflight, traveling to and from the lunar orbit – or cislunar space – would help NASA and its partners acquire knowledge and experience necessary to ultimately venture beyond the moon. Roscosmos and NASA already work together with other space agencies around the world to run research projects aboard the International Space Station (ISS).

“While the deep space gateway is still in concept formulation, NASA is pleased to see growing international interest in moving into cislunar space as the next step for advancing human space exploration,” Robert Lightfoot, NASA’s acting administrator, said in a statement.

A lunar space station would be the type of infrastructure that could serve as a stepping stone for future crewed missions to Mars. The US agency has been quite outspoken on its ambitions to send humans to orbit Mars by the 2030s, and the Trump administration is in favor, as the Guardian reports.

Although the main works are scheduled to begin in the mid-2020s, it is necessary to note that the plans are not concrete at this point. NASA says it will continue to work with Roscosmos to research the best ways to transport astronauts to and from lunar orbit.

NASA is also asking the private space industry to contribute to the deep space gateway. The agency has already awarded contracts for deep space habitat designs to Bigelow Airspace, Lockheed Martin, Orbital ATK and others, Space.com reports.