At the 68th International Astronautical Congress being held in Adelaide in Australia this week, Russia is expected to announce that it will be joining the NASA-led project to build a human space-outpost that will orbit the Moon.
The project is known as the Deep-Space Gateway and a number of international partners, such as the Japanese, Canadian, and European space agencies, will be collaborating on the construction of this modular outpost which plans to be orbiting the Moon at some point in the early 2020's. Once established this new outpost will be placing humans beyond the Earth's orbit for the first time since the Apollo Moon missions.
Since the outpost will be put in place using NASA's SLS rocket as well as Orion spacecraft it will be laying the foundations for future missions to Mars. Elon Musk's plans to go to Mars do rely on an orbital fuelling station, it is not clear whether this outpost has anything to do with those plans.
Roscosmos has been considering a number of other space projects lately, their main goal appears to be a manned moon-base with which the near-lunar Deep-Space Gateway may now appear to be a helpful collaboration since NASA has agreed that the gateway can be used as a platform to make moon landings from.
Russia is also expected to sign a major deal in October with the Chinese on future moon missions which in addition to collaborating with other international partners on the Deep-Space Gateway might give their moon-base ambitions a greater chance. The Russian agency was also contemplating making their own ISS-like earth-orbiting space station but has now decided that this will be too expensive to do at the same time as their moon-base project.
With the Russians on board, the Deep-Space Gateway may benefit immensely from their expertise in rockets, lander development, and modules for the outpost itself.