MOSCOW, January 22. /TASS/. The United States denied an entry visa to Russian cosmonaut Nikolay Chub, who was to undergo training at NASA's Johnson Space Center, a source familiar with the situation told TASS on Saturday.

"Without explaining its reasons, the United States denied an entry visa to Roscosmos cosmonaut Nikolay Chub, whose flight to the ISS is scheduled for spring 2023. He planned to visit the US in order to participate in a training session at the Johnson Space Center," the source said.

Russian state-run space corporation Roscosmos did not comment on this information to TASS.

Training of foreign astronauts at Russia’s Yury Gagarin Cosmonaut Training Center and of Russian cosmonauts at the Johnson Space Center is a routine practice, giving space crews knowledge of the US and Russian segments of the International Space Station. Such training sessions are held regardless of what kind of spacecraft will be used to deliver cosmonauts and astronauts to the orbit.

Nikolay Chub is a member of the backup crew of ISS Expedition 68, which is to fly to the orbital outpost aboard the Soyuz MS-22 spacecraft in September 2022. He is also a member of Expedition 69’s main crew, to be delivered to the ISS by a Soyuz MS-23 spacecraft next spring.