CFB VALCARTIER, Que. - On a day of grim news from Afghanistan, Defence Minister Peter MacKay delivered a blunt message to the U.S. and other NATO allies.

If they're looking for more troops, they shouldn't look to Canada.

MacKay says he hasn't felt any direct pressure from the U.S. government yet for Canada to extend its combat mission beyond 2011.

But if that day ever comes, MacKay says Canada has already done its share and plenty of other countries should be approached instead to step up.

"I think there's a continued call to NATO allies for them to contribute more," MacKay told a news conference Tuesday.

"But there are many countries in line before Canada that should be approached before they would come knocking on our door, I would suggest to you."

The comments come as senior U.S. military officers are going public with their demand for more troops, and admitting the conflict is not going well for NATO.

That reality was underscored Tuesday by spectacular explosions in the province where Canadian soldiers are based.

Five car bombs detonated simultaneously in Kandahar -- killing dozens of people, injuring dozens more, and reducing a construction company office to rubble.

This occurred on the same day that preliminary results from Afghanistan's presidential election suggested a close race between incumbent Hamid Karzai and his main challenger.

MacKay called the contrast -- election results emerging on the same day as deadly bombings -- symbolic of the Afghan situation.

"We're obviously awaiting the results of the election . . . and we've made tremendous contributions there," he said.

"Yet we hear today, and I would express on behalf of all Canadians our respect and solidarity and our condolences to those that were affected, (about) today's blast in Afghanistan that took the lives of many.

"This is symbolic of the continued challenges that exist on the ground in Afghanistan."

Canada has been involved in Afghanistan since 2001.

Although insurgencies elsewhere in the world have only been defeated following lengthy conflicts that have dragged on for years or even decades, the government says Canada can't commit to Afghanistan forever.

The Obama administration is expected to push Canada to remain beyond 2011.

But if the White House intends to do any such diplomatic arm-twisting, MacKay says he hasn't seen it yet: "There hasn't been any direct approach in that regard," he said.

If that American request ever arrives, officials say Canada already has its answer planned: No.

It's the same response delivered last month when the head of NATO, Anders Fogh Rasmussen, declared his wish that Canada remain.

"You saw the response we gave the NATO secretary-general," said one Canadian government official.

"Our response is not going to be different for anybody on Earth."

"Our response was delivered by Parliament."

Parliament has approved a resolution that Canada's combat mission in Afghanistan will end in 2011, although the government says some soldiers and Canadian civilians might stay behind to do logistical or aid work.