You can tell you’ve left the American segment of the International Space Station (ISS) and entered the Russian segment when the walls go from white to salmon-colored. It’s a singularly unlovely salmon, and if Russian designers had to do it over again perhaps they’d have picked up a different can of paint. Either way, the color had a meaning: the U.S. and Russia—old Cold War rivals—might be cooperating in space, but this part of the giant station was still Russian soil.
This week, that fact took on more than just symbolic meaning, when Yuri Borisov, the newly appointed head of Roscosmos, the Russian space agency, emerged from a meeting with Russian President Vladimir Putin with word that the 24-year partnership Moscow and Washington have maintained, building and operating the ISS, was coming to an end.
“The decision to leave the station after 2024 has been made,” Borisov said. “I think that by that time we will start forming a Russian orbiting station.”
The announcement was both a surprise and not a surprise. The aging ISS has long been scheduled to be decommissioned and deorbited by 2024. But lately, NASA and President Joe Biden have been working on plans to extend the station’s operation until 2030. The 15 partner nations that control the ISS—which, in addition to the U.S. and Russia, include Canada, Japan, and eleven countries that are part of the European Space Agency (ESA)—would have to agree to the extension. And as Reuters reports, they had been scheduled to take up that very topic at a regularly scheduled meeting today. But Borisov’s comment has thrown all of that into question—and for more than just political reasons.
The station is composed of 17 habitable modules—six provided by Russia, eight by the U.S., two by Japan, and one by the ESA. The modules serve as laboratories and dormitories for the crew, with the U.S. and Russian segments performing three critical additional functions: The U.S. is responsible for maintaining and operating the wings of solar panels that provide the station with power, as well as operating the gyroscopes that keep the ISS stable; the Russian segment is responsible for periodically boosting the station’s orbit with bursts from the engines of an attached Progress cargo vehicle, which prevent the faint atmospheric drag—present even at the 402 km (250 mi.) altitude at which the station flies—from pulling the station out of the sky. Without the cooperation of both countries, the station would be doomed.
NASA put the best face possible on Borisov’s statement, pointing out that neither the White House nor the space agency had been formally notified of the pullout plans—and there may be a good reason for that. Russia has plans to build its own space station, named ROSS, which it hopes to have flying by 2028. The day after Borisov’s announcement, the Roscosmos website published an interview with Vladimir Solovyov, an ISS flight director, in which he said, “We, of course, need to continue operating the ISS until we create a more or less tangible backlog for ROSS. We must take into account that if we stop manned flights for several years, then it will be very difficult to restore what has been achieved.” In the wake of Borisov’s threat, that’s diplomatic-speak for, “Never mind.”
If Russia is indeed back-pedaling, that’s a very good thing. The hot war in Ukraine, like the Cold War in the 1950s and 1960s, has made relations between the U.S. and Russia an ugly thing to watch. It was in space—first with the joint Apollo-Soyuz mission in 1975, then with space shuttle flights to Russia’s now-deorbited Mir space station in the 1990s, and now with the ISS—that the two countries could join hands. That grip has helped keep the peace for decades. It would be a pity—and a peril—to break it now.
This story originally appeared in TIME Space, our weekly newsletter covering all things space. You can sign up here.
Write to Jeffrey Kluger at firstname.lastname@example.org.