Adil Charkaoui says he was kicked off an Air Canada flight after U.S. officials made the plane return to N.B. after crossing into American airspace. (Ian Barrett/Canadian Press)

U.S. authorities ordered an Air Canada flight carrying a Montreal man accused of having terrorist links back to New Brunswick, where he was ordered off the flight, the man said Thursday.

Adil Charkaoui was returning to Montreal from Fredericton on June 3 as part of a cross-country tour to denounce Canada's security certificate process and restore his reputation.

The landed immigrant from Morocco spent two years in Canadian detention on a ministerial security certificate after his 2003 arrest on suspicion of links to al-Qaeda. Charkaoui, who denies having any links to the terrorist group, was released under tight restrictions two years later, including wearing a GPS locator on his ankle.

Charkaoui says he was about 45 minutes into the flight, which crossed into U.S. airspace, when U.S. officials ordered it to turn back to New Brunswick.

He and two agents from the Canada Border Services Agency who were accompanying him were removed from the flight when it landed in Fredericton.

Charkaoui and the two agents then drove the roughly 700 kilometres back to Montreal.

U.S. had cleared flight

An Air Canada spokesperson refused to give a recorded interview, but did say the plane was forced to turn around after U.S. authorities rescinded an agreement to let Charkaoui fly.

However, Air Canada spokesperson Isabelle Arthur told Canadian Press by email that the flight "had been cleared by the American authorities prior to takeoff (but) was subsequently refused entry into U.S. airspace and therefore had to return to Fredericton."

She referred all further questions to U.S. authorities.

Charkaoui, who kept the incident secret until it was leaked to the media this week, says someone is trying to smear his reputation. He says the airline told him someone called U.S. officials about his presence on the return flight, even though he had obtained permission from Transport Canada and the Canada Border Services Agency.

When asked about the incident Thursday during a news conference in Halifax at Pier 21, Prime Minister Stephen Harper said Canada regularly co-operates with "our American friends" on matters of security.

This country, he says, must respect its security obligations, including the fact that Charkaoui is on a U.S. no-fly list.

But Charkaoui says he's not impressed by that argument.

"I think that the prime minister should care about Canadian lists, not U.S. lists," he said.

'We need … facts'

The Canadian Border Services Agency released a statement saying it has been and will remain diligent in monitoring Charkaoui, including ensuring he respects the terms and conditions imposed by the Federal Court.

Charkaoui has called for an inquiry into the June 3 incident.

"I'm asking the Canadian government to have a full inquiry to know who called the Americans…. We are going to bring the issue in front of the federal courts. We need to have the facts."

The Canadian Security Intelligence Service contends the school teacher and part-time graduate student is an al-Qaeda sympathizer who should be sent back to Morocco.

Last June, the Supreme Court of Canada criticized CSIS for destroying the original evidence behind its allegation that the Montreal father of three is a terrorist.

In February, the Federal Court eased some of the restrictions on Charkaoui, meaning he's able to go out unsupervised and is allowed access to the internet on his home computer, although he is closely monitored.

With files from The Canadian Press