A US astronaut and two Russian cosmonauts will take off on a Russian-operated flight to the International Space Station on Wednesday, despite rising tensions between Moscow and Washington over Russia’s invasion of Ukraine.

According to Russia’s space agency Roscosmos, NASA’s Frank Rubio and Russians Sergey Prokopyev and Dmitry Petelin are scheduled to lift off at 1354 GMT from the Russian-leased Baikonur Cosmodrome in Kazakhstan.

Rubio will be the first US astronaut to fly to the ISS on a Russian Soyuz rocket since President Vladimir Putin dispatched troops to pro-western Ukraine on February 24.

In response, Western capitals, including Washington, have hit Moscow with unprecedented sanctions and bilateral ties have plummeted to new lows.

However, space has managed to remain an outlier of cooperation between the two countries.

Following Rubio’s flight, Russia’s only active cosmonaut, Anna Kikina, is expected to travel to the orbital station aboard a SpaceX Crew Dragon in early October.

She will become only the fifth professional cosmonaut from Russia or the Soviet Union to fly into space, and the first Russian to fly aboard a spacecraft operated by SpaceX, the company owned by US billionaire Elon Musk.

With both flights scheduled to go ahead, Russian cosmonauts and western astronauts have tried to avoid the conflict raging on Earth, especially when in orbit together.

A collaboration between the United States, Canada, Japan, the European Space Agency and Russia, the ISS is divided into two sections: the US orbital segment and the Russian orbital segment.

Currently, the ISS depends on a Russian propulsion system to maintain its orbit about 250 miles (400 kilometers) above sea level, with the US segment responsible for electricity and life support systems.

But tensions in the space arena have risen after Washington announced sanctions on Moscow’s aerospace industry – prompting warnings from Russia’s former space chief Dmitry Rogozin, an ardent supporter of the Ukraine war.

Rogozin’s recently appointed successor, Yuri Borissov, later confirmed Russia’s long-discussed move to exit the ISS after 2024 to create its own orbital station.

The US space agency Nasa called the decision an “unfortunate development” that would hinder scientific work on the ISS.

Space analysts say building a new orbital station could take more than a decade and Russia’s space industry – a point of national pride – may not thrive under heavy sanctions.

The ISS was launched in 1998 at a time of hope for cooperation between the US and Russia following their Cold War space race competition.

During this period, the Soviet space program flourished. It boasted a number of achievements, including sending the first human into space in 1961 and launching the first satellite four years earlier.

But experts say Roscosmos is now a shadow of its former self and has suffered a series of setbacks in recent years, including corruption scandals and the loss of a number of satellites and other spacecraft.

Russia’s year-long monopoly on manned flights to the ISS has also gone to SpaceX, along with millions of dollars in revenue.