The Conservatives unveiled three new television ads Sunday attacking Liberal leader Stéphane Dion, a day before members of Parliament return to the House of Commons.
The English-language ads, which will be followed by a second series of French ads, assert that Dion is a weak leader who would take the country back to the past.
The Conservative ads use footage from the Liberal leadership debate.
CBC
They also criticize Dion's record as environment minister, charging that greenhouse gas emissions went up and air quality went down under his watch between 2004 and 2006.
In response to the ads, Dion told CBC News, "[Harper] wants to spend all this money to try to attack me in a very negative way, and it'll backfire."
"Canadians will not be impressed by that."
Dion also criticized Harper's environmental record, saying that several months ago the prime minister said that greenhouse gas emissions didn't exist.
The ads use footage from last fall's Liberal leadership debates, including clips of Michael Ignatieff, now Dion's deputy leader, and Ken Dryden admitting that the Liberals failed to meet the Kyoto targets for emission reductions.
One ad includes a clip of Dion plaintively responding to attacks on his environmental record, telling Ignatieff he doesn't know how hard it is to set priorities.
B.C. Conservative MP James Moore said, "We think that Stéphane Dion has been getting a little bit of a free ride. We're going to hold him accountable for the things he didn't do as environment minister."
The Conservatives, who have secured a prized spot for the ads during next weekend's Canadian broadcast of the Super Bowl, refused to say how much the party is spending on the election-style campaign.
With files from the Canadian Press
The Conservative Party of Canada have taken a new approach by launching a new ad campaign. It is aimed at the Liberal Party of Canada leader Stéphane Dion.

The ads, which will frequently be aired during next weekend's Canadian broadcast of the Super Bowl, criticizes Dion as a leader and also criticizes his past in the government, as Canada's environment minister. They also feature clips from the Liberal leadership debate last fall. The ads are in English but another set of ads will air in French speaking Quebec, Dion's home province.

The Conservative Party of Canada logo.
Dion, who was elected Liberal leader in December, responded to ''CBC News'' saying that it will "backfire" on Stephen Harper.

"Harper wants to spend all this money to try to attack me in a very negative way, and it'll backfire," Dion said. "Canadians will not be impressed by that." "Mr. Harper has nothing positive to say about his own record."

One ad says that air quality deteriorated when Dion was environment minister. The second ad says that he wants to go back to the previous Liberal government. The third ad says that he is not a leader.

The main ad is entitled "Stéphane Dion Is Not A Leader".