Conservative Leader Stephen Harper said Canadians have a clear choice in the upcoming election between his party's "sensible balance" approach to governing and the Liberals' "untested schemes."

Harper, speaking during a campaign stop in Richmond, B.C., said the Tory campaign will be based around "affordable promises."

"We cannot, we will not, get into a bidding war with the opposition," said Harper. "That is a fundamental choice in this campaign -- do we stay the course or do we go back to an agenda of tax and spend."

He said Canadians would risk their "standard of living with expensive, ill-defined, untested schemes" if they elected the Liberals.

"They've made it clear that they favour a higher GST (and) they promised to scrap the $100 per month -- $1,200 per year -- child care benefit," said Harper.

He also banged away at the Liberals' carbon tax policy.

"They're asking Canadians to sign up for a permanent new category of taxation -- the carbon tax," said Harper.

He said it was "a tax that Canadians will pay on tax, on top of all of the taxes they already pay, on top of sales taxes, income taxes, investment taxes, business taxes and every other fee, charge or premium levied by governments."

Earlier Monday, the Tories unveiled new attack ads saying the Liberal policies will hurt all Canadians and punish the middle class.

One of the ads shows Liberal Leader Stephane Dion's face spinning on a slot machine and says his carbon tax plan will mean higher gas prices, higher electricity rates and higher grocery bills for Canadians.

"Can you afford higher everything?" asks the announcer.

Dion responds

During a campaign stop in St. Lambert, Que., Dion accused Harper of spreading lies about the policies of the Liberal Party.

He said the Tories are lying when they say the Liberals would raise the GST and cut the child care payment.

"They are piling their lies upon lies," said Dion. "They are unable to stop to lie."

Dion also said Harper called an election because he was scared of losing upcoming byelections and of scandals being exposed in his government.

He said Harper was also scared about the direction of the economy.

"His direction is a recession, his direction is a deficit," Dion told reporters. "His direction is a mess that he's giving to this economy."

Dion said the Tories have no plan for the economy and that their record is one of failure.

"Only us as Liberals know exactly how to manage the economy," he said.

The Liberals also issued a press release Monday calling on Harper to "publicly commit that his party will not use the same spending scheme that Canada's Elections Commissioner is currently investigating from the last election."

Canada's elections watchdog is trying to determine if the Tories broke regulations in the way they paid for local and national advertising.

In a letter sent to the prime minister yesterday, Dion urged Harper "to publicly pledge to refrain from repeating any of these suspect financial practices in the spirit of democratic fairness during the writ period."

Meanwhile, NDP Leader Jack Layton was in the Northwest Territories Monday saying he wants to shut down further expansion of Alberta's tar-sands development.

Layton, who will later go to Vancouver, also promised to force big oil companies to clean up and reclaim land used for petroleum production.

Speaking to CTV's Canada AM on Monday, Layton said his campaign will focus on issues that affect Canadians such as the rising price of gas and post-secondary education.

"The issues that people deal with at the kitchen table with their families... are the ones that I think Parliament should be debating right now," he said.

Green Party Leader Elizabeth May camapaigned in Ottawa, visiting a soup kitchen as a backdrop to talk about poverty.

With files from The Canadian Press