About 950 Canadian soldiers will remain in Afghanistan after 2011 to serve as trainers, where they will teach Afghan soldiers in classrooms and on bases.
The soldiers will train Afghan forces until 2014.
Details about the extended mission are to be settled in discussions with other countries engaged in Afghanistan. The government is expected to reveal details at a news conference Tuesday.
The CBC's Laurie Graham reported that the end of the combat mission is expected to taper off, rather than ending suddenly. The transition could take about six months, from July to December 2011, as combat soldiers become full-time trainers.
Canadian soldiers will no longer be mentoring in the field, but teaching Afghan soldiers only in classrooms and on bases.
The government has said the training will take place in Kabul, a calmer area than Kandahar where Canadian forces are now engaged in the front-line fight against the Taliban. But the door is open to Canadian soldiers being stationed around the country, Graham said.
Details about the future mission emerged following question period, when the opposition parties grilled the Conservatives, demanding details on the extension of Canada's mission in Afghanistan past the previously established deadline of next July.
Liberal Leader Michael Ignatieff said Canadians want a clear, detailed position on the new mission.
"How many people will be there to train these people?" Ignatieff asked. "Does this role exclude combat? Where will the training take place? Behind the wire [security perimeter] or not? Will these people be in Kabul?"
Foreign Affairs Minister Lawrence Cannon said Afghanistan remains Canada's main priority with respect to international security and that the Canadian effort in Afghanistan will continue in a non-combat capacity. He did not provide details about the number of troops who would remain in Afghanistan or their exact role.
"These answers are genuinely absurd," said Ignatieff. "We are five days away from [NATO's] Lisbon summit, and the government is unable to stand up in the House and tell us exactly what the post-2011 combat mission looks like."
However, a Conservative MP later said the government has not yet determined the scope of the mission.
"The final details are still under consideration," Tom Lukiwski, who is also the parliamentary secretary to House leader John Baird, told CBC's Power & Politics with Evan Solomon.
No Liberal-Conservative pact to extend mission: Rae
Liberal MP Bob Rae asked about the length and cost of the new mission.
Cannon said Canada will stay on in Afghanistan in a non-combat role until 2014 and that additional details will be announced at the appropriate time.
Earlier in the day, NDP Leader Jack Layton said he wants a parliamentary debate on extending the mission in Afghanistan to allow MPs and Canadians to "debate the stark choices."
Prime Minister Stephen Harper and Ignatieff both broke promises on the length of the Afghan mission, Layton said in Ottawa. He accused them of reaching "what appears to be a secret agreement to extend our military engagement by three years in this war that has already gone on for nine years."
Rae responded to the accusation of a Tory-Liberal pact after question period.
"I was in the House of Commons today, asking questions to which we wanted answers. So, it's clear there's no kind of deal going on," he said.
"Why aren't they giving you answers to your questions? One can only assume that they're not ready yet to give us the answers to the questions."
There was a vote in Parliament in 2006 and another in 2008 on the Afghan mission, and there should be one now, the NDP is arguing.
Layton suggested the government has not acted responsibly in the past week as news of the extension surfaced.
"The soldiers have done their fair share with honour," said Layton, adding Canada should be focusing on improving living conditions in Afghanistan.
Canadians would weigh in strongly against the mission extension if it were put to a parliamentary debate, said Layton. The NDP argues that since soldiers would be engaged in combat training, the new mission is just an extension of a military mission in a war zone.
Layton said the choice of spending billions of dollars on combat training "or investing in diplomacy, in civilian efforts" must be debated.
In question period, he said the government has broken promises and has refused to take part in a democratic exercise. He suggested that there would be risk to troops even in a training role.
Cannon pointed out there was no vote taken in the House when troops were sent to Haiti, for example, after the devastating earthquake in January.
No vote needed
Assigning a training and technical mission — as opposed to a combat mission — is within the authority of the prime minister, making a vote unnecessary, Harper said ahead of the G20 meeting in Seoul last week. Harper was not in question period.
Liberal MP John McCallum, a defence minister under Jean Chrétien, said more details about Canada's new role are needed but not a vote.
"What we have said is we want to see the details but that there doesn't necessarily have to be a vote," McCallum said. "I think the resolution in Parliament was to end the combat mission, and the combat mission will be ended.
"We want to see how many people are involved, where they will be, what they will be doing. We want details on that. But I wouldn't say, necessarily, that there has to be a vote on a non-combat training mission."
Defence Minister Peter MacKay did not speak on the Afghan matter in the House. Rumours surfaced last week that MacKay was hoping to leave politics.
"This is not the time for the minister of defence to be going AWOL," Rae told reporters after question period.
NATO has yet to announce firm plans on troop levels and what exactly it wants from the Canadian Forces, but its meeting in Portugal starting on Friday will focus on Afghanistan.
The Conservative government has been facing international pressure to leave behind military trainers once its combat mission ends in July to help address a shortfall in the NATO-led mission.
Reported plans have Canada reducing its current deployment of about 2,700 troops in Afghanistan to roughly 750 military "trainers" and another 250 military support staff. The government has not offered exact numbers.
This all comes amid recent comments by Afghan President Hamid Karzai suggesting that coalition troops end night raids, which cause friction between Afghans and foreign troops.
Karzai told the Washington Post the time has come to reduce military operations and the "intrusiveness into the daily Afghan life."
He said the long-term presence of so many foreign soldiers will only make the war worse.