OTTAWA — The spiralling cost of the Afghan war has added unknown factor into an unpredictable election that appeared solely concerned with voters’ fears about the economy and collapsing stock markets.

Parliamentary Budget Officer Kevin Page injected the cost of the war into the waning days of the election campaign by reporting that taxpayers will pay between $14 billion and $18 billion — and possibly more — by the time troops are withdrawn in 2011.

That’s about $1,500 for every Canadian household, and well above any estimates so far released by the government.

Opposition leaders treated the news with care, but nevertheless accused Prime Minister Stephen Harper of failing to come clean with Canadians about the true financial costs of a mission that has so far claimed 97 Canadian lives.

But Harper staunchly defended the spending, saying the government will spend whatever is necessary.

“When we have men and women in uniform, diplomats and development workers who are putting their lives on the line, the government will spend what is necessary to make sure they are safe and successful,” he told a news conference in Victoria.

Five days before Canadians vote, it is unclear whether the war, which has hardly been discussed during the campaign, will play a significant role in voters thinking at a time when uncertainty about the economy remains high.

Harris-Decima pollster Bruce Anderson said while the new costing is an inconvenience for Harper, much will depend on whether the opposition parties “shift their main ballot focus” from the economy to the war.

Not surprisingly, the strongest reaction came from Bloc Quebecois Leader Gilles Duceppe, who is fielding candidates only in the province with the most entrenched views against Canada’s military mission.

“It’s too much and not balanced at all,” he said, noting that only nine per cent of the spending is going to humanitarian aid, while 91 per cent is for the military operations and veterans’ benefits.

“It’s tied to the ideology and strategy imported from the Bush Republicans in the United States with those disastrous results.”

Having supported the extension of the mission to 2011, Liberal Leader Stephane Dion restricted his criticism to accusing the Conservatives of not being forthcoming with Canadians about the war costs.

Most of the party leaders continued to pound on their familiar positions on the economy, a tactic that polls suggest has been successful in turning the election from what appeared to be a decisive Tory victory to what even Harper now acknowledges is a close contest.

The latest Canadian Press Harris-Decima four-day rolling poll suggested Harper had arrested his recent slide in national support, putting the Conservatives at 32 per cent support, followed by the Liberals at 27 per cent and the NDP at 19.

The prime ministers has taken a battering the past few days for sounding insensitive about the losses in Canadians’ savings wiped out by the stock market plunge.

But he appeared on more solid ground Thursday armed with a World Economic Forum report that gives Canada’s banking system a gold star, rating it the soundest in the world.

Harper also pounced on a International Monetary Fund report that predicted Canada would not fall into recession, outperforming the U.S. next year with modest growth.

Canada does have tightening credit markets making it more difficult for individuals and businesses to borrow, he said, but Canada’s banks are sound and the economy is growing.

“There is no question, no possibility of bailing out the banks,” Harper said. “The banks aren’t seeking to be bailed out and the government won’t be bailing them out.”

Earlier, Finance Minister Jim Flaherty said the government will do whatever is necessary to ensure there is sufficient liquidity in Canada’s money markets so that credit does not dry up and stall economic activity.

The IMF and banking reports appeared to put Dion on the defensive on economic issues.

“I never said we’ll have for sure a recession, I said we’ll avoid one if we have a government who works with Canadians to make sure it will not happen,” he said.

Before the prime minister spoke from Victoria, the finance minister was meeting with reporters in Ottawa attempting to show that the government does sympathize with Canadians over their lost savings.

“Canadians are seeing dramatic losses in their savings and their retirement investments. People are worried about the global economy and its effects on Canada,” Flaherty said at a news conference in Ottawa.

“They are also worried about their job security, worried about their homes. I share their concerns.”

Both Flaherty and Harper expressed regrets that the banks had not passed through to customers the full half-point interest rate cut announced by the Bank of Canada on Wednesday.