A New Democratic government would launch a national prescription drug program and reform drug patent laws to make medication more affordable to Canadians, NDP Leader Jack Layton pledged on Friday.

Speaking in Vancouver, Layton also promised his party's platform, to be released on Sunday, will be fully costed and will not take Canada into a deficit.

The NDP drug proposal calls for the federal government to implement a so-called catastrophic drug transfer to provinces and territories, as recommended by former Saskatchewan premier Roy Romanow's 2002 report into the Canadian health-care system.

The transfer to provinces and territories would start at $1 billion for the first year and increase gradually as finances permit, Layton said.

The New Democrats would also create a national bulk purchasing program, he said.

He compared the drug proposal to Tommy Douglas's battle to build Canada's medicare system, and he slammed Conservative Leader Stephen Harper for giving $50 billion in tax breaks to wealthy corporations "while prescription drug costs break family budgets."

"Mr. Harper will ridicule us as usual," Layton said. "I remember that people said to Tommy Douglas that medicare couldn't be done.… Don't let anyone tell you that it can't be done."

Speaking in Toronto on Friday, Liberal Leader Stéphane Dion lambasted the billions of dollars pledged by Layton during the campaign, saying the numerous NDP spending commitments are being made "with monopoly money."

Layton's pledge, part of the NDP's platform for the Oct. 14 election, comes a week after a study funded by pharmaceutical companies ranked Canada 17th of 18 OECD countries in public spending on pharmaceuticals. 

It was Layton's second straight day in British Columbia, where polls indicate support for the New Democrats has been growing amid a tight battle with the Conservatives. 

Star candidate's tarsands comments scrutinized

Layton came to the defence of one of his star candidates in the province after he strayed from the party's official environmental policy during a local debate.

While speaking about climate change, Michael Byers, an expert in international law and politics who is running in the riding of Vancouver-Centre, said: "We need to shut the tarsands down."

The New Democrats' policy is to end subsidies for companies operating in the tarsands but not to force their closing.

When asked about the candidate's comments on Thursday, Layton said he was sure he and Byers were on the same page.

"I've been very clear on my position, and I'm sure Michael supports it," Layton said.

But Dion quickly jumped on the comments, saying they showed "the NDP cannot be a party that we consider seriously."

Dion campaigns for rival-turned-backer

Dion began his day in the Toronto riding of Parkdale-High Park, where his one-time leadership rival, Gerard Kennedy, is running. The Liberals hope to win back the district after losing it in the 2006 election to NDP candidate Peggy Nash.

The Liberal leader pushed his message to a group of seniors, saying his party's platform is the best way forward in a time of economic uncertainty.

Less than an hour later, Dion asked Winnipeg-area candidate Lesley Hughes to step down over past comments she made suggesting Israeli companies had been given a heads-up ahead of the Sept. 11, 2001, hijackings in the United States.

Also on Friday, Green Leader Elizabeth May's cross-country rail tour continued with a number of stops in towns across Ontario, before ending the day with a stop in Charny, Que.

Bloc Québécois Leader Gilles Duceppe was to campaign in Warwick and Drummondville, both in Quebec.

Do you have a question for Elizabeth May? Send it to national@cbc.ca for The National's Your Turn with the Green party leader on Monday.