As Canada prepares to pull its CF-18s out of the air mission against the Islamic State group and triple its efforts on the ground, Defence Minister Harjit Sajjan says the military's new role will carry greater risks, but that it is "what the coalition needs."

Prime Minister Justin Trudeau announced last week that his government plans to halt Canadian airstrikes against ISIS militants by Feb. 22.

Instead of continued airstrikes, the government says it will triple the size of its "train, advise and assist effort" on the ground. Canada will also keep one refuelling plane and two surveillance aircraft in the region.

"The plan that we have put into place by adding more, tripling the trainers, is what the coalition needs," Sajjan told CTV's Question Period. "Training the local security forces is absolutely necessary for retaking the ground that Daesh (the Islamic State group) has taken, and for the eventual destruction of the enemy."

Canada already has 69 special forces trainers working in Iraq, and some critics have voiced fears that increasing that number will also raise the risk of Canadian casualties.

Sajjan said the new approach will be riskier, but that it is part of Canada's duty to support the international coalition fighting ISIS.

"Yes, it is more risky, just for the simple fact of having more troops on the ground," he said. "But we've always been a responsible coalition partner, and we look at the needs of the coalition and this plan fills those gaps."

And if Canadian troops do come under attack, Sajjan said they will have the right to fire back.

"It is a conflict zone in a high-threat environment," he said. "If unfortunately they've been put in a situation, they will defend themselves. We have robust rules of engagement to help them protect themselves."

In addition to committing more troops to the "train, advise and assist" effort, the Canadian government has committed $840 million in humanitarian aid to the region over the next three years. It has also pledged $270 million to help countries that have absorbed Syrian refugees.

Back from a recent trip to the Middle East, International Development Minister Marie-Claude Bibeau said Canadian aid is helping to provide food and health services to refugees in Jordan.

"I witnessed that our money was very well utilized," she said.

'Extremely disappointed': Opposition critics express concern

Both the CF-18 pull-out and plan for increased presence on the ground have drawn criticism from opposition parties.

Conservative Defence Critic James Bezan said his party is "extremely disappointed" that the Liberals are abandoning the airstrikes.

"They never gave a reason why Canada had to stop bombing," Bezan told CTV's Question Period. "Because Canada's withdrawing, that responsibility has shifted to other allies and it's hurting our reputation internationally."

Meanwhile, NDP Foreign Affairs Critic Helene Laverdiere challenged the Liberal claim that the new role is a "non-combat" mission.

While Sajjan insisted that Canadians will not be the "principle combatants," Laverdiere raised safety concerns.

"We've already lost military personnel, Sgt. (Andrew) Doiron, on the front line and now we're going to have even more boots on the ground," she said. "It does look like a combat mission."

Green Party Leader Elizabeth May also said Canada's new military role will mean troops are more likely to find themselves in combat roles.

"The reality of boots on the ground is, yes, that the Canadian troops who are going to be working with the Kurdish Peshmerga are clearly going to find themselves in combat situations," she said.

With files from The Canadian Press