Reda Hassaine, 46, was instrumental in the arrests of Abu Qatada and Abu Hamza al-Masri, who were indoctrinating Muslims and recruiting young men to join al-Qaida and the Taliban, The Times of London reported.
He began working for Scotland Yard's Special Branch in 1998 and then later for the domestic MI5 intelligence agency. While no contract was signed, he was paid $600 per month plus $160 for expenses through 2000.
He told the newspaper he and his family had been offered "the safety and protection of British citizenship," but only his former wife and children were granted citizenship.
"First I was discarded and now I've been frozen out," Hassaine said. "I am not asking for any reward now. All I want is the security and safety that was promised."