MONTREAL - The federal Liberals have picked a former journalist to run for the party in a Montreal byelection.

Jocelyn Coulon, who is currently a professor at the Universite de Montreal, makes regular appearances on Quebec TV stations to comment on international events.

Liberal Leader Stephane Dion trotted out Coulon at a news conference Friday in the riding of Outremont, which has been vacant since former Liberal transport minister Jean Lapierre quit politics earlier this year.

Coulon predicts Canada's mission in Afghanistan will be at the centre of the next general election as well as the upcoming byelection.

He called on Prime Minister Stephen Harper to tell NATO allies that Canada will not extend its mission after February 2009.

"We have made an extraordinary effort,'' Coulan said. "We are demanding that our allies reposition their troops in Afghanistan.''

Dion said Coulan entered politics to help stop the Conservative government's "Republican-Bush'' approach.

"What the voters of Outremont will have as an opportunity in the coming weeks will be to think about the possibility to give to Canada one of its best experts to help Canada to stop what Mr. Harper is trying to do to our country, and his name is Jocelyn Coulon,'' Dion said.

Harper has about another week to set a date for the byelection.

The Conservatives have not yet chosen their candidate, while former Quebec environment minister Thomas Mulcair will run for the New Democratic Party.

The Bloc Quebecois will be represented by Jean-Paul Gilson.