OTTAWA -- The Opposition New Democrats pledged Wednesday to keep the government's feet to the fire over Canada's new combat mission to Iraq but they turned down the heat considerably.

The last few weeks have been characterized by nearly relentless political pressure on the Conservatives to detail plans for Canada's military to join an international air strike campaign against extremists.

Yet the tone of debate in the aftermath of Tuesday night's vote to send Canadian fighter planes and surveillance aircraft into the skies against Iraq was less intense.

New Democrat Leader Tom Mulcair said nothing has changed in terms of his party's position.

"We have the greatest respect individually for the brave women and men who serve in our military, but that doesn't mean that we now agree with the government's decision on this mission," he told reporters Wednesday.

"We firmly and continually disagree with the mission they've put forward."

Mulcair said it was his role to keep at Prime Minister Stephen Harper for more details.

"I'm going to continue asking the questions that I have to ask as leader of the opposition, that's my role here in Parliament, holding the government to account, saying what we would do differently," he said.

"We're going to continue to do that. We hope that the government is a bit more forthcoming than it has been."

Mulcair half got his wish -- Harper did reveal some new information during question period in terms of where the planes are coming from.

Up to six CF-18s will be deployed from 4 Wing Cold Lake, one CC-150 Polaris will be deployed from 8 Wing Trenton and two CP-140 Auroras will be deployed from 14 Wing Greenwood, the government confirmed.

Where they are going remains unknown.

"The military is continuing to work on the deployment plan and I'm not at a position at this point to confirm where that deployment will be," Harper said.

The government motion expressly excludes the potential of joining any ground combat mission in Iraq, though it did extend the deployment of special forces working as advisers to Iraqi and Kurdish forces battling back the Islamic State of Iraq and Levant.

ISIS is a splinter group of al Qaeda now waging a brutal campaign against religious minorities and women in Iraq and Syria in order to gain control of territories there.

The U.S. began a bombing campaign against their positions in Iraq in August. Nations including Britain and France have now joined, using similar justifications as Canada's that the Iraqi government has asked for help to beat back ISIS.

But as the campaign moves into Syria, several nations have backed away from air strikes there, fearful of any action that could be seen in support of Syrian President Bashar Assad, reviled by much of the West for his role in the brutal civil war in that country.

Canada, however, has left the door open to dropping bombs if Assad were to request assistance.

The NDP have repeatedly questioned that decision and it also caused one Liberal MP to break ranks with his leader's assertion that caucus would vote unanimously against the mission.

Prominent Liberal MP Irwin Cotler explained Wednesday he had no choice but to abstain.

He has been calling for air strikes on Syria for years, he noted, but the notion of carrying them out at the request of the Syrian government defeats the purpose.

"I could never support this resolution put forth by Harper because he made it contingent on the acceptance by Syrian President Assad for those operations -- the very person against whom I said military operations should be convened in order to hold him accountable for his war crimes," Cotler said.

Trudeau rejected the notion that Cotler's abstention reflected on greater divisions within his caucus, saying they had had a robust discussion prior to the vote.

"We feel that Canada does have a role to play in the push against ISIL," Trudeau said.

"However, we could not support the government's plan last night. We have a different idea of what is necessary."