The Bloc Quebecois and Parti Quebecois say sovereignty would solve two of Quebec's main problems -- the environment and the fiscal imbalance.

"In a sovereign Quebec, we wouldn't have this debate over fiscal imbalance, the Kyoto protocol would be implemented," PQ Leader Andre Boisclair told reporters in Montreal on Sunday.

"They don't agree, as we do agree, on every issue," Bloc Leader Gilles Duceppe told reporters about the federalist parties after his meeting with Boisclair.

"Just take the fiscal imbalance. There's a big difference between Quebec's demands and (Prime Minister Stephen) Harper's answers in Ottawa."

The Bloc has demanded $4 billion for the fiscal imbalance in the next federal budget or it will vote against it.

Quebec's Liberal Premier Jean Charest, a former federal Progressive Conservative leader, has said he expected Prime Minister Stephen Harper to act on the imbalance. While Charest is a Harper ally, he is pro-Kyoto, the global climate change accord.

Charest has until 2008 to call a provincial election, but has hinted he could drop the writ this spring.

Boisclair said his party has 50 candidates nominated and money in the bank to fight a vote when it comes.

Both Duceppe and Boisclair hope a provincial vote precedes a federal one, so the PQ can put its election machine to work for the Bloc.

The seat distribution in Quebec's 125-seat national assembly is as follows: Liberals, 72; PQ, 45; Action democratique, 4, one independent and two vacancies.

There is speculation the federal Conservative minority government could fall this year, with the government losing confidence over its budget.

However, a veteran Quebec Liberal MP who is leaving politics doesn't think that's likely.

I wouldn't worry about the Bloc," Jean Lapierre told CTV's Question Period. "I don't think (Liberal Leader Stephane) Dion wants an election. He said it publicly that he's in no rush and the NDP will be fighting for its survival, so I don't think this next budget will have a problem going through."

The Conservatives, with 125 seats, can survive with the support of the NDP, which has 29 MPs in the 308-seat House of Commons. The Bloc, Liberals and two independents don't have enough seats to guarantee defeat of the government.

NDP Leader Jack Layton has tried to pressure the federal Conservatives over its environmental legislation and noted that the Conservatives have tried cozying up to his party.

"I notice they're trying to hug us. What I say is stop trying that. Why not just try to deliver on the environment and on some fairness for the average Canadians for a change?" Layton told Question Period.

Asked if he would be prepared to defeat the Conservatives over the budget this spring, he said, "We haven't seen the budget yet."

Layton noted that his party voted against last year's federal budget and that the Bloc supported it.

With a report from CTV's Graham Richardson and files from The Canadian Press