MONTREAL - Former British prime minister Tony Blair accepts Canada's decision to scale back to a training role in Afghanistan, but he points out that an extremist threat still exists and countries must be ready to confront it.

Blair spoke briefly to a roundtable of journalists after the official announcement Friday of an alliance between his foundation and Montreal's McGill University.

Prime Minister Stephen Harper confirmed Thursday that Canadian troops will stay in Afghanistan to train the country's military after the current combat mission ends in July.

Blair told The Canadian Press that Canada's military has done a fantastic job in Afghanistan.

"They're hugely respected there," he said.

"It's a decision for Canada to take. It's absolutely got the right to do what it wishes to do in respect to this."

However, he cautioned there is still work to be done in fighting terrorism.

"My view about the broader question of extremism, though, is that this extremist security threat is still absolutely a threat we face," he said.

"It's in many, many different parts of the world and we have to be prepared to confront it and to realize it will take a long time to do it."

The Faith and Globalization Initiative, part of the Tony Blair Foundation, aims to educate people about different religions to reduce fear and build mutual understanding.

Several major international universities, including Yale in the United States and Peking University, will do research into questions about the impact of religion in society.

McGill is the only Canadian university participating.

Ironically, Blair's visit to Montreal comes shortly after his sister-in-law announced her conversion to Islam, calling on him in the British press to change his presumptions about the Muslim faith.

Lauren Booth, a vocal opponent of the war in Iraq and former reality show contestant, accused Blair of believing Muslims are bad.

Blair and an adviser smiled ruefully Friday when Booth's name was raised and, after pointing out she was his wife's half-sister, the former prime minister said he would stick to his stock reply when it came to her.

"My reaction is always the same to what she says, which is she's entitled to her views."

Blair preached religious tolerance during the encounter and during a discussion and question-and-answer period earlier.

He said it's essential that the leaders of today and tomorrow have a grasp of religious questions.

"My point is very simple -- if you want to be a leader today, in politics, in business, in civic society, you cannot be religiously illiterate," Blair said.

"You've got to know about it. You may not agree with it, you may not even like it but you've got to know about it."

Blair cited his work in Jerusalem as a special peace envoy, saying that while there are political and security concerns, the religious dimension of the Israel-Palestine question, for example, cannot be ignored.

He also cited other situations where religious ignorance had led to intolerance, such as so-called Islamophobia.

Blair said that to have a cohesive society, there has to be a recognition of diversity but also a common space where people put their separate identities aside in obedience to law and such things as equality.

He noted, for example, that a citizenship requirement for immigrants to Britain is that they be able to speak English.

Blair, who was prime minister from 1997 to 2007, said he felt that when he was in office he could have used advice and assistance from the academic world in framing the intellectual debate around religious and cultural issues.

"This is complicated and profound stuff about the nature of our society," he said, noting similar debates are going on all over the world.

"The people who are the practising politicians actually know this issue is really important today because they can feel the pressure within their own constituencies and their own countries," he said later in response to an audience question.

He added that politicians often find they aren't very well informed in dealing with such questions.

Blair, who released his memoirs in September, hadn't had a chance to read former U.S. president George W. Bush's new book but he said: "I'm sure I will."

The former Labour leader only seemed flummoxed on one question during the event, when he was asked by a Montreal reporter whether polygamy would ever be legalized in Britain.

He said he didn't think it would ever happen in his country, adding, "My wife wouldn't be very happy about that."