The UK’s Special Immigration Appeals commission denied an Afghan-born man his appeal to keep his British citizenship after it was rerevoked due to allegations that he is a Russian spy, in a judgment handed down on Friday.

The appellant, known as C2, was born in Afghanistan but moved to Russia briefly to avoid being drafted. He married a Russian woman, and the two claimed asylum in the UK in 2000. He was granted citizenship in 2007 and worked for Britain in Afghanistan. His citizenship was revoked pursuant to section 40(2) of the British Nationality Act 1981 on the basis that he was “assessed to be an agent of the Russian Military Intelligence Service (GRU) and pose[ed] a threat to UK national security.”

The appeal was brought under section 2B of the Special Immigration Appeals Act 1997 (the SIAC Act 1997) on two grounds: “the decision that C2 poses a threat to national security is irrational, and the decision was procedurally unfair and was made in breach of natural justice in that SSHD failed to give C2 an opportunity to make representations prior to the making of it”.

The court dismissed the appeal and found that C2 was an unreliable witness, that there were “conflicting accounts of how he got to Russia” and that based on the evidence before it, the conclusion of SSHD’s judgment that “C2 was an agent of the GRU as at September 2019 is amply justified.”

The UK and Russia have had a tense relationship recently over accusations of Russian espionage, with UK Home Secretary James Cleverly announcing on Wednesday that the country will expel an “undeclared” Russian military intelligence officer, accusing a diplomat of espionage.