(CNN) Russia says it is planning to pull out of the International Space Station and end its decades-long partnership with NASA at the orbiting outpost, according to the newly appointed head of Russia's space agency.
Roscosmos chief Yury Borisov told Russian President Vladimir Putin that "the decision to leave this station after 2024 has been made."
"You know that we are working within the framework of international cooperation at the International Space Station. Undoubtedly, we will fulfil all our obligations to our partners, but the decision to leave the station after 2024 has been made," Borisov told Putin in the Kremlin-issued readout.
NASA said in February it intends to keep operating the International Space Station until the end of 2030, after which the ISS would be deorbited and crashed into a remote part of the Pacific Ocean. Commercially operated space platforms would replace the ISS as a venue for collaboration and scientific research, NASA said.
But Robyn Gatens, director of the International Space Station for NASA, said that NASA hadn't received any official word from Russia about the decision to quit the ISS.
"The Russians, just like us are thinking ahead to what's next for them. As we are planning transition after 2030 to commercially operated space stations in low earth orbit, they have a similar plan. And so they're thinking about that transition as well. We haven't received any official word from the partner as to the news today, so we'll be talking more about their plan going forward, " Gatens said.
"NASA is committed to the safe operation of the International Space Station through 2030, and is coordinating with our partners," NASA administrator Bill Nelson said in a statement. NASA has not been made aware of decisions from any of the partners, though we are continuing to build future capabilities to assure our major presence in low-Earth orbit."
State Department spokesperson Ned Price said news that Russia will withdraw from the International Space Station is "an unfortunate development given the critical scientific work performed at the ISS, the valuable professional collaboration our space agencies have had over the years, and especially in light of our renewed agreement on space-flight cooperation."
This is not the first time that Russia has threatened to abandon the ISS amid crippling US and European sanctions over the war in Ukraine. Borisov's predecessor, Dmitry Rogozin, repeatedly threatened to do so before he was ousted earlier this month.
Scott Kelly, an American former ISS commander, believes the announcement may be mere posturing.
"I believe Russia will stay as long as they can afford to because without ISS they have no human spaceflight program," he said.
"Cooperation with the West also shows some amount of legitimacy to other non-aligned nations and to their own people which Putin needs as the war in Ukraine has damaged his credibility. The design of the ISS makes it difficult for the remaining nations to operate the ISS if either Russia or the US was to withdraw but not impossible. Also, 'after 2024,' is vague and open ended so I think this could be just more bluster," he added.
But this most recent threat has more teeth, and the apparent approval of Putin himself. According to the transcript of a meeting posted to the Kremlin's website, Putin said "good" after Borisov told him that Roscosmos will begin to build its own space station after 2024.
Former NASA associate administrator Doug Loverro said that he believes the threat to withdraw from the ISS is real, and possibly a reflection of internal Kremlin politics.
"I think you can read this as a pre-planned follow-on to replacing Rogozin. If he had said this, it would look like just one more bluster statement. But this is the new guy, presumably very close to Putin, saying this one week after taking over. I think it is real." Loverro said.
Russia's withdrawal would be a major blow to the ISS, a model of international cooperation for decades.
The news comes less than two weeks after NASA and Roscosmos announced a crew-exchange deal or "seat swap" that had been under negotiations for more than four years. Starting in September, two Russian cosmonauts will launch on US spacecrafts from Florida while two American astronauts will ride Russian rockets into space. It's unclear if Russia's decision to pull out of the ISS after 2024 will impact the crew-exchange agreement.
The ISS, which is a collaboration among the US, Russia, Japan, Canada and the European Space Agency, is divided into two sections -- the Russian Orbital Segment and the US Orbital Segment. The Biden administration announced in December that it was committed to extending the ISS from 2024 to 2030. But Russia -- NASA's number one partner at the ISS -- never signed onto it.
"The Russian segment can't function without the electricity on the American side, and the American side can't function without the propulsion systems that are on the Russian side," former NASA astronaut Garrett Reisman told CNN in February. "So you can't do an amicable divorce. You can't do a conscious uncoupling."
Since then, NASA has been exploring ways of moving the space station without the assistance of the Russian segment. In June, a Cygnus cargo spacecraft demonstrated its ability to raise the station's orbit. But whether the ISS would be able to survive without the Russians is still an open question.
And the US is making contingency plans in case Russia follows through with its publicly stated intention of withdrawing after 2024.
"That's the responsible thing to do," NSC communications coordinator John Kirby said.
He said the US remained committed to working with all International Space Station partners but was taking prudent steps to prepare for a possible Russian withdrawal.
Launched in 2000, the ISS has orbited 227 nautical miles above Earth with more than 200 astronauts from 19 different countries enjoying stints aboard -- representing a continuous human presence in space.
China, whose astronauts have long been excluded from the ISS, launched the second module of its space station this week. While not as large as the ISS, the Chinese space station is expected to be fully operational by the end of this year.