MONTREAL -- The New Democrats and Liberals are "enemies" of an independent Quebec, and only his party can be trusted to defend the province's interests in Ottawa, Bloc Quebecois Leader Gilles Duceppe said Tuesday.

In a phone interview with The Canadian Press, Duceppe ramped up his attacks against his two main opponents in Quebec as part of a campaign that refuses to concede Quebecers are less interested in his Bloc than ever.

"For people who want a country, it's a good idea to vote for people who want a country," Duceppe said. "It's a mistake for people to vote for the enemies of the country they want."

When presented with a report demonstrating the NDP supported 39 of 45 unanimous motions adopted by Quebec's legislature over the past four years, Duceppe responded: "It's not 100 per cent, like the Bloc would have."

The Liberals have now promised to do what the Bloc has been proposing for years -- invest massively in public infrastructure to stimulate the economy -- but the Bloc leader refused to give his Liberal counterpart, Justin Trudeau, any credit.

"I want to see where the money will come from," he said, dismissing Trudeau's pledge to run deficits if needed to finance a stimulus package. "I'll comment on it when I see their financial plan."

Duceppe brushed off suggestions his party was not only losing support among sovereigntists but also from the Quebec media, which have so far expressed no interest in buying seats on his campaign tour bus.

"Journalists have less money than before, so they don't want to rent a place in our bus," Duceppe said. "But there are some who asked to come with us during the day. We'll give them a lift."

Duceppe reserved his sharpest criticism for NDP Leader Tom Mulcair, whom he trashed for supporting Philippe Couillard, leader of the Quebec Liberal party, during the 2014 provincial elections.

He suggested Mulcair -- a former Quebec provincial cabinet minister -- was hypocritical for criticizing Conservative Leader Stephen Harper's "austerity" measures, but voting provincially for a party that also cut government spending.

"The NDP is against Harper's austerity but for the austerity of Couillard," Duceppe said.

"Mulcair has always been a man of the right. He was known to be part of the right-wing section of the Quebec Liberal party."

The NDP leader was also an "enemy" of Quebec's strict language legislation when he was a lawyer for a now-defunct English-language rights lobby group, Duceppe said. Mulcair has said New Democrats are very much in favour of Quebec's language legislation, known as Bill 101.

Despite his brave front, Duceppe and the Bloc have to grapple with the growing possibility that the party could be swept from the province after the Oct. 19 vote. The NDP is as popular -- if not more popular -- than in 2011, when it took 59 of 75 seats in the province.

He refused to say what a poor showing would mean for the provincial Parti Quebecois and for sovereignty itself.

"I am not a prophet," he said.

Duceppe said there are more than 50 days left in the campaign and the Bloc is currently where the NDP was in the polls a few weeks before the 2011 election.

"The NDP reversed (the poll numbers) then and we'll reverse them back this time," he said.