Collins John is eligible to play for Barnet after the League Two club finally received international clearance following his move.
The 26-year-old former Fulham player joined the Bees last month but the Underhill outfit had been waiting on paperwork from the Iranian FA.
Head coach Mark Robson said: "It's been an extremely long two weeks waiting for Collins' clearance.
"We are all relieved that another piece of the jigsaw is in place."
He added: "Collins is an experienced player and we look forward to having him available."
John could be included in the squad for Barnet's home game against Plymouth Argyle on Saturday.