Premier Jean Charest and federal Liberal leader Stéphane Dion took turns berating Pauline Marois on Wednesday, accusing the Parti Québécois leader of trying to take a back-door route to Quebec independence.

Marois's intention to seek more powers from Ottawa if the PQ returns to power will only lead to uncertainty for the province, Charest said as he attended a party caucus meeting in Sherbrooke, Que.

"Madame Marois is announcing five years of disruptions before a referendum takes place," Charest said.

Marois has said she would like to see Quebec get its own constitution and citizenship and take over a number of powers from the federal government.

The premier said he is amazed by Marois's approach and said it is clear to him the PQ is being radicalized to please its hardline elements.

Dion also scoffed at Marois for saying she would negotiate new power-sharing agreements with the federal government if the PQ forms the Quebec government.

"The question of power sharing between the federal and provincial authorities has but one purpose: to better help the population," Dion said in Quebec City on Wednesday.

"If something is better managed by the provinces, then there will be a new division. But it is not to please a separatist leader who says it will be another step toward dismantling the country."

Dion said he thought the independence movement had a "responsible" leader in Marois but no longer believes that given her recent comments about wanting to pursue the sovereigntist path that Quebecers have so far rejected.

If Marois wants to be responsible, he said, she has to convince Quebecers they would be better off outside Canada. Efforts to take the province out of the country by "the back door" would be futile, he said.

"The only acceptable democratic practice is to say: 'I am going to convince people, and once they become convinced, I will hold a referendum with a clear question."'

Dion scoffed at suggestions by Marois and the Opposition Action Démocratique du Québec (ADQ) that Quebec needs its own constitution.

He said any such constitution would only be a provincial document and would have no real clout.