New Democrat Leader Jack Layton demands an emergency debate in the House of Commons on April 5 on the Canadian mission in Afghanistan over concerns about the changing nature of the mission and the treatment of detainees.

"When the decision was made, actually in the middle of the election, that through NATO there would be a new deployment and Canadian soldiers would be sent to the south of Afghanistan, we suggested at that time it would be important to have a debate as soon as Parliament could convene," Layton told CTV's Question Period on Sunday.

"We need to support our troops by making sure that we're very, very clear as Canadians what the mission is and, of course, it originally was supposed to be a NATO mission, but NATO has not taken charge yet."

Layton said Canadians need to know how long troops would be in Afghanistan and what the exit strategy is.

Both Prime Minister Stephen Harper and Defence Minister Gordon O'Connor have said that there would be no new debate on the Canadian mission.

Canada has more than 2,000 troops in Afghanistan and is supporting a provincial reconstruction team in the danerous area around Kandahar.

The NDP leader also expressed concerns "there's been an agreement signed with the government of Afghanistan, this was done under the Liberals, and our military leadership, to turn over prisoners to the Afghan government."

Layton said this raises concerns over the treatment of detainees who could be tortured by the Afghan government or turned over to the Americans.

He admitted, however, that he had no evidence that this was happening and had not read the agreement.

Foreign Affairs Minister Peter MacKay, also appearing on Question Period, said he was not aware of the agreement of which Layton spoke. 

MacKay said that there has been an agreement since December with NATO to turn over prisoners to Afghan autorities. O'Connor told Question Period last week that detainees would be turned over to the Afghans.

Layton said: "(We) believe there was a different agreement that was signed between our military leaders at the time of the Liberal administration and the Afghan government.  That's what's got to be talked about in Parliament."

The Foreign Affairs minister, however, said defence staff would not be able to enter into an agreement with the Afghan government without consulting the Prime Minister and Defence Minister.

Layton underlined that he was not alleging that Canadian troops were complicit in the potential mistreatment of detainees.

"What we're interested in seeing is the agreement that's been signed regarding the transfer of detainees.  I can tell you that in other countries there's extensive public debate about this because there's concerns about humans rights issues ... Canadians would want to know that we're always sticking with the letter of the Geneva Conventions."