PQ leadership favourite André Boisclair has admitted that he used cocaine during the years he served as a cabinet minister in the Quebec government.

The acknowledgment comes just weeks before Parti Québécois members choose a new leader.

André Boisclair speaks at the launch of his Parti Québécois leadership campaign in June (CP Photo)

Boisclair admitted he used cocaine in the years during which he was a PQ cabinet minister, between 1996 and 2003. But he didn't want to discuss when he consumed coke, with whom he did it, and from where he got it.

"What I want to tell you is I made mistakes, things I regret. Yes, I consumed. I can't be clearer than that," Boisclair said Monday.

He called his past drug use a regrettable mistake he made in his youth. He said he doesn't use coke now, and he was never impaired on the job.

"I've never had problems of consumption," Boisclair said in Lévis, Que. "I have never been in a situation where I was under the influence of anything when I carried out my responsibilities as a member of the legislature or as a cabinet minister."

Michel David, a political columnist with Montreal's La Presse, said the admission of cocaine use while in office places Boisclair in trouble. "Maybe he was young, but he was a young cabinet minister, and that's the whole point," David said.

"How much, from now on, is André Boisclair a political risk, both for the PQ and for the sovereigntist movement?"

Boisclair is one of nine candidates vying to replace Bernard Landry as PQ leader in November.