"The United States has issued an entry visa to Roscosmos cosmonaut Nikolai Chub. The cosmonaut is headed to the United States for training at the Johnson Space Centre, which all cosmonauts traditionally undergo before ISS flights," Roscosmos said in a press release.
Late last week, Chub's US visa application came back refused without any explanation. Roscosmos head Dmitry Rogozin said he would address the issue with NASA chief Bill Nelson.
A spokesman for the US embassy in Moscow, Jason Rebholz, said the diplomatic mission is making every possible effort to continue issuing visas to Russian cosmonauts amid a personnel shortage.