Liberal Leader Michael Ignatieff pledged Wednesday to erase the projected $50-billion federal deficit if elected into government -- and to do so without raising taxes.

Ignatieff held a news conference in Sudbury, Ont., offering more details about why he has decided to no longer support the Conservative government and outlining the tack he will take if an election is triggered.

On Tuesday he said the Liberals would bring down the government at the first opportunity, though they will need help from the NDP and Bloc to do so.

Ignatieff said Wednesday that Canadians have lost faith in the Conservatives' fiscal management skills.

"Remember the record. They offered us a budget with a deficit of $32 billion, that's a big number. Six weeks later it jumped to $50 billion," Ignatieff said.

"So there's a question not just about the size of the budget but the basic competence of Jim Flaherty and Stephen Harper."

Ignatieff said a Liberal government under his leadership would re-focus the government's stimulus spending to promote exports and open border crossings.

A Liberal government would also eliminate the deficit without reaching into Canadians' pockets, he said.

"We will not come to the Canadian public with proposals that break the bank. Remember we've been here before, we inherited a $42-billion deficit from Mr. Mulroney and we had to clean it up and we did so without raising taxes," Ignatieff said.

"We've inherited a $50-billion hole from Mr. Harper and we will clean it up without raising taxes."

When pressed on how he would do that, Ignatieff would only say: "wait and see."

Earlier Wednesday, Liberal MP Bob Rae called the Conservative government incompetent, ideological and bad, and justified a bid to bring down the minority Parliament by saying it's his job to try to do so.

Rae said the Official Opposition has supported the minority government of Stephen Harper through a time of uncertainty and change, but it's now time for action.

"I didn't come to Parliament to vote for Stephen Harper, I wasn't elected to vote for a neo-conservative government," Rae told CTV's Canada AM.

"I'm a member of the Official Opposition, Mr. Ignatieff is the leader and he's said we're not going to continue to support the government."

'Political opportunism'

Conservative Transportation Minister John Baird defended his party on Wednesday morning, saying the Liberals have supported the party -- or abstained from voting against it -- on every vote for the past three years.

He called the recent move "political opportunism at its worst."

"Mr. Ignatieff was very clear this week in a moment of candour, when he said 'we will do it when it suits us.' Well it's not all about Mr. Ignatieff and the Liberals, it's about Canadians."

Baird said the economy is in a fragile state and the timing is simply wrong for the fourth election in five years -- one he said few Canadians want.

He was echoing the words of Prime Minister Stephen Harper who on Tuesday said Canadians elected the Conservative minority government less than a year ago, and want the government to focus on the economy, not an election.

Political gamble

CTV's Roger Smith, reporting from the Liberal caucus meeting in Sudbury, said Ignatieff's announcement went against the advice of many people within the party.

"It's a huge gamble for him, it's a roll of the dice," he told CTV News Channel.

"Michael Ignatieff, for all his other skills this is his first campaign, he is untested, and a lot of Liberals are saying he has one shot at this, he is 62 years old, he gets one shot and he's gambling that this is his best shot now."

The NDP's Thomas Mulcair on Tuesday suggested there might be room for co-operation with the Conservatives, to avoid an election.

However Baird pointed out that the NDP voted against the Conservatives on 79 occasions, and suggested the party would only side with the Conservatives if doing so resulted in a political payoff.