Michael Ignatieff is dismissing the NDP's budgeting as "science fiction" as the Liberals launched an all-out assault on Jack Layton.

The NDP is now taking heat from all sides as the Liberals, Conservatives and Bloc Québécois try to push Canadians away from Layton's party with more polls suggesting increasing support for it.

The Liberals put out anti-Layton radio and internet ads on Saturday as Ignatieff went to Halifax to press the Liberals' pitch for better access to prescription drugs.

"It's time to take a close look at what Jack Layton is saying to the Canadian people. The numbers add up and up and up and up. And we're saying take a look at the program. We've got a costed program, we don't make any promises we can't keep," Ignatieff said.

"We can tell you exactly we won't raise taxes, and Mr. Layton has got a platform which when you look at it closely has simply $30 billion of spending which we think is not going to be good for the economy and he derives it from sources we just don't think are credible … it's science fiction."

The Liberals also put out a statement arguing the NDP plan to raise money through a cap-and-trade system on carbon emissions won't work since it would take years to implement.

Ad attacks 'inexperience'

The latest attack ad from the Liberals aims to dispute any attempt by Layton to portray himself as an outsider to the system, noting his 26 years in politics. At the same time, it also labels his party's candidates as "inexperienced."

The ad also targets the NDP's spending promises and suggests the party is not showing a "principled" position in support of the federal gun registry.

The previous parliamentary session saw several NDP members from rural and northern ridings vote with the Liberals and Bloc Québécois to block a Conservative attempt to scrap the gun registry. Layton faced blistering criticism from the Liberals and the Bloc for allowing his members a free vote on the issue. 

In an interview that aired Saturday on CBC Radio's The House, Layton said he believes the apparent increase in support is due to Canadians taking a second look at his party's "very practical proposals" as well as a growing sense of disenchantment with the status quo in Parliament.

"We’re just going to keep working hard to build on that momentum, saying to people you’ve got a real choice in this election," he told host Kathleen Petty.

"Ottawa needs to be changed and we’re inviting you to join with us to make this change happen."

GTA battleground

Meanwhile on Saturday, Conservative Leader Stephen Harper and Ignatieff were back on the campaign trail after a brief break for the start of the holiday weekend, while Layton was seeking to build momentum with campaign stops in the Toronto area and Montreal.

Harper continued his push for a majority goverment during a campaign event in Mississauga, Ont.

"It doesn’t matter what the combination is of the opposition," Harper said Saturday. "We need to put an end to minority Parliaments and elect a strong Conservative majority government."

An online survey done by CROP, which cannot be assigned a margin of error because the methodology doesn't allow for random sampling, suggested the NDP had the support of 36 per cent of respondents in Quebec, compared to 31 per cent for the Bloc Québécois.

A poll from Nanos, meanwhile, showed the NDP gaining in support nationally, but the sample size for Quebec was too small to give results within an acceptable margin of error.

The new polls prompted a release by the Conservatives of a fresh attack ad aimed squarely at Layton. The ad slams Layton as "blindly ambitious" and willing to conspire with the Bloc to form a government.

In the 2008 election, it says, "Layton began planning a coalition with the Bloc Québécois before our votes were even counted." It finishes: "He did it before. He'll do it again. And Canada will pay the price."

On Friday, New Democrat Paul Dewar dismissed it as being based on "complete fabrications," and called on the Tories to pull the ad.

Ignatieff will campaign in Nova Scotia and Prince Edward Island before wrapping up the day with a stop in Mississauga, where he will attend an Easter service in the Church of the Virgin Mary and St. Athanasius.

Meanwhile, Green Party leader Elizabeth May will campaign through B.C., with stops in Saanichton and North Saanich.

With files from The Canadian Press