But Palfreeman, speaking under a portrait of revolutionary Che Guevara which he kept in his cell to keep his spirits up, said he had doubts he would be allowed to leave.

"They could come and arrest me in five minutes," the bearded Palfreeman told Reuters in the office of his Bulgarian Prisoners' Association.

Palfreeman co-founded the association to draw attention to alleged abuse and corruption in the prison system.

He has consistently maintained he acted in self-defence, trying to protect minority Roma being attacked by a group of Bulgarians. He believes video footage of the attack, released by an anonymous user on YouTube, will support his case.

"I believe a fair trial would be possible," he said. "I can speak Bulgarian, I can defend myself because 13 years ago I couldn't speak Bulgarian. I didn't know what was happening and there were a lot of things I missed because of the language barrier."

Palfreeman said he was "completely shocked" by the systemic lawlessness in Bulgarian jails, adding that 90 per cent of prisoners were not allowed to do any work.

Palfreeman, who was serving in the British army at the time of the street fight, said a motion for a new trial was expected to be filed on Monday.

Reuters