09/18/2015 01:29 EDT | Updated 09/18/2016 05:12 EDT

Mulcair Won't Say How Oil Prices Could Affect NDP Fiscal Framework

"Our approach ... is sustainable and it is transparent."

REGINA — Tom Mulcair unveiled Friday a multi-billion-dollar plan to drive down the price of prescription drugs but questions persisted about how the he'd pay for that and other pricey promises when his balanced budget pledge is based on outdated economic assumptions.

The NDP leader's fiscal framework is based on assumptions used in the 2015 federal budget presented last April, including $67-per-barrel oil and relatively robust economic growth. Since then, the price of oil has collapsed to about $47 per barrel and growth has stalled.

Mulcair wouldn't say Friday how he would alter his fiscal framework if the price of crude continues to languish at about $47, as some analysts predict.

"Our fiscal plan that was put forward was based on the best projections of Canada's finance ministry, backed up by the most recent analysis by the parliamentary budget officer," Mulcair said.

"Our approach ... is sustainable and it is transparent."

Mulcair acknowledged that the price of commodities goes up and down.

"That's something Mr. Harper never predicted himself, he never banked on that ... We are being prudent in our approach," he said, calling on Harper and Liberal Leader Justin Trudeau to reveal the fiscal framework for their platforms.

Mulcair said he spoke Thursday with Kevin Page, the former parliamentary budget officer, who congratulated him for releasing the NDP's cost analysis and for being both prudent and transparent.

"He loved the fact that the NDP was going ahead and publishing a fiscal framework, and of course, he said that we're being very prudent in our assessment."

That seemed at odds with comments Page made in a Huffington Post story, which quoted him as saying the NDP's financial document was thin, full of holes and could be "all fantasy" if one believes the budget economic assumptions on which it's based are already outdated.

In an interview, Page said Mulcair's description of their conversation is "bang on" — as far as it went. He said he gave the same analysis to both Mulcair and the Huffington Post, outlining the positive and potentially negative aspects of the NDP's fiscal framework, in terms of whether it's realistic, prudent, sustainable and sufficiently detailed.

But while the news outlet focused on the negatives, Page said "it's very fair to say" that Mulcair chose to focus on the positives.

Mulcair went to a Liberal-held riding in Regina to announce he plans to work with the provinces on universal prescription drug coverage — but the party is not classifying the promise as a national pharmacare plan. He promised $2.6 billion over four years aimed at achieving universal access.

The NDP says it will also aim for a 30-per-cent average reduction in the cost of prescription drugs through bulk purchasing programs.

"With a national plan, we can drive down the cost of prescription drugs for Canadians and we can save provinces as much as $3 billion annually," Mulcair said.

"I am a former provincial cabinet minister and I know, I'm confident that this kind of support will help the provinces and the provinces will welcome the direct aid that I am talking about."

Provincial health ministers have been pressuring Ottawa to introduce a full-fledged national pharmacare program.

Mulcair held Friday's event in the riding of Regina-Wascana, which has been held by Liberal Ralph Goodale since 1993.

Goodale, a former finance minister, criticized the NDP's financial analysis of the all Mulcair's promises.

"These are glaring errors in Thomas Mulcair's costing," Goodale said in a statement.

"Mulcair is doing the same old political thing: promise a bunch of things you know you can't do. Then after you get elected, say things are much worse than you thought and you can't do what you promised."

The riding is one of only two Prairie seats retained by the Grits in 2011.

The NDP hopes to improve its electoral fortunes in Saskatchewan, where it was shut out last time.

Former NDP MP Lorne Nystrom, who served in the Commons for 32 years, said he believes the party will benefit from changes to riding boundaries, which split previously mixed ridings into separate urban and rural constituencies.

"The last campaign we had 33 per cent of the vote in the province and the Liberals had about 10 per cent," Nystrom said.

"They got one seat and we got none and the Conservatives got 13 because of the way the boundaries were drawn ... now, with the new drawing of the boundaries, if we transfer that vote to the new boundaries, we would have three seats just based on status quo."

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