The United States and Russia have agreed to fly each other's spacefarers to the International Space Station (ISS). The agreement comes after months of tensions and ambiguity surrounding collaborative space activity in the aftermath of the war in Ukraine.

Both Russia's Roscosmos and NASA stated on Friday that they had reached an agreement on the so-called "integrated flights."

The ultimate purpose of the agreement is to ensure that at least one US astronaut and one Russian cosmonaut be present at the ISS to maintain respective sectors of the station, according to Roscosmos.

“The agreement meets the interests of Russia and the United States and will promote the development of cooperation within the International Space Station program framework,” the agency said in a statement.

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According to NASA spokesman Josh Finch, "flying integrated crews ensures that there are suitably trained crew members on board the station for crucial maintenance and spacewalks."

Finch stated that the agreement is a "no-exchange-of-funds arrangement" that includes all essential training as well as "transportation to and from the International Space Station and extensive mission support."

“It also protects against contingencies such as a problem with any crew spacecraft, serious crew medical issues, or an emergency aboard the station that requires a crew and the vehicle they are assigned to return to Earth sooner than planned,” he added.

First joint flight 

The first flight under the agreement, which will feature NASA astronaut Frank Rubio and Russian cosmonauts Sergey Prokopyev and Dmitry Petelin, is scheduled for late September. The crew will go to the ISS aboard the Russian Soyuz spacecraft.

Another trip, also scheduled for October, will use a US Crew Dragon spacecraft. According to Roscosmos, the trip will most likely include Anna Kikina, Russia's only active female cosmonaut.

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The apparent breakthrough in NASA-Roscosmos connections comes after months of difficulties caused by the two countries' deteriorating relationship.

The announcement of the agreement also coincided with the dismissal of Russia's long-serving space head, Dmitry Rogozin, who was replaced in a government reshuffle on Friday by Yury Borisov.