Foreign Affairs Minister Peter MacKay has again denied a passport to Abdurahman Khadr, a former terrorism suspect who was captured in Afghanistan and held for months in Guantanamo Bay, Cuba.

MacKay's decision comes despite a Federal Court of Canada ruling that Ottawa must stop rejecting Khadr's applications, The Globe and Mail reported Wednesday.

Khadr, a 24-year-old Canadian citizen, was released from Guantanamo Bay -- where he was being held as an enemy combatant -- after agreeing to spy for the U.S.

He has never been charged with a crime, but hasn't been allowed to obtain travel documents necessary to leave Canada.

Prime Minister Stephen Harper defended MacKay's decision and said it was justified.

"Minister (Peter) MacKay has taken his decision based on national security according to his powers and responsibilities," Harper said Wednesday. "Mr. Khadr has the right to appeal that decision."

The court ruled on June 8 that Ottawa had insufficient grounds to deny Khadr's applications, and he should be provided with the same "fairness and legitimate expectation owed to all Canadian citizens."

The decision opened the door for Khadr to again apply for a passport, which he did. That application has now been denied, however.

"It's not only our national security, it's the national security of other countries," a senior government official told The Globe. "And it goes to the integrity and the responsibility that goes with carrying a Canadian passport."

Khadr is one of Ahmed Said Khadr's four sons. The Egyptian-born Canadian and accused al Qaeda financier was killed during a gun battle with Pakistani forces in 2003.

The family patriarch was also alleged to be an associate of accused terrorist mastermind Osama bin Laden.

At one time or another, each of the family's five siblings, all Canadian citizens, have been accused or investigated for alleged links to terrorism.

Karim Khadr, 15, lives in Scarborough. A bullet wound in the gun battle with Pakistani security forces in which his father died left Karim paralyzed.

Omar Khadr, 19, is being held in the American detention facility at Guantanamo Bay, Cuba. U.S. officials have charged him with murder in the death of a U.S. medic in Afghanistan during a 2002 gun battle.

Abdullah Khadr, the eldest son in the family, is also being held in Canada, and is trying to fight extradition to the U.S. on charges that he supplied weapons to al Qaeda and plotted to kill Americans abroad.

He claims Canadian and U.S. officials turned a blind eye while he was tortured and raped in a Pakistani jail.