U.S. Defence Secretary Robert Gates meets with Gen. David McKiernan, commander of the International Security Assistance Force (ISAF) and commander of the U.S. forces in Afghanistan, at Kandahar Airfield on Thursday. (Scott Olson/Pool/Associated Press)

Canada's defence ministry has ruled out extending its combat mission in Afghanistan past the 2011 scheduled deadline despite hints from U.S. Defence Secretary Robert Gates that Ottawa should reconsider its end date.

"Nothing has changed since the parliamentary motion was passed," said Dan Dugas, a spokesman for Defence Minister Peter MacKay. "We're done with the Kandahar combat mission in 2011."

Ottawa's response follows comments made Thursday by Gates, who was asked by a reporter whether Canada should continue its mission.

"The countries that have partnered with the United States and Afghanistan here in [regional command] south have made an extraordinary commitment, and proportionately, none have worked harder or sacrificed more than the Canadians," said Gates, who arrived at Canada's main base in Kandahar on Thursday.

"They have been outstanding partners for us, and all I can tell you, as has been the case for a very long time, the longer we can have Canadian soldiers as our partners, the better it is."

Dugas said that Gates has "always been gracious about Canada's role in the UN-mandated mission."

But he added that "the minister and government have been very clear that Parliament has decided that our mission there ends in 2011."

During the election campaign, Prime Minister Stephen Harper reaffirmed that he will abide by a motion passed in the House of Commons that Canada would withdraw the bulk of its military forces in Afghanistan as scheduled in 2011.

CBC's David Common said Gates comments should not be considered a formal request, but that they are significant because the defence secretary is staying on in that role under Barack Obama's administration. As well, the president-elect has said getting more troops to Afghanistan is a priority.

Gates also told reporters that the Pentagon will move three brigades into Afghanistan by next summer, the most specific he's been on when he'd begin meeting the requests of ground commanders asking for 20,000 troops.

The extra troops are expected to be deployed to Kabul to secure the capital before moving to Kandahar, considered the epicentre of violence and where most of the 2,500 Canadian soldiers in the region are based.

Gates said he will not have to cut troop levels further in Iraq to free up at least two of those three brigades for Afghan duty.

He also said the mission needs to focus better on building the Afghan army and better co-operation with Kabul on security operations.

"I think there's a concern on the part of some of the Afghans that we sort of tell them what we're going to do, instead of taking proposals to them and getting their input and then working out with them what we're going to do, so it's a real partnership," Gates said. "That's an important aspect of this, that I think we need a course correction."

With files from the Associated Press