Canada's Trudeau smoked pot while an MP

Canada's Liberal leader and strong candidate for prime minister, Justin Trudeau, admitted Thursday that he has smoked marijuana since being elected to parliament, after recently calling for legalizing its use.

The eldest son of late prime minister Pierre Trudeau told the Huffington Post that he smoked pot five or six times in his life, the first while on a trip to the Caribbean with university classmates and most recently three years ago with friends over for a dinner party while his children were staying overnight with their grandmother.

The admission was made in an interview with the news website, which was conducting a survey of Canadian lawmakers' drug habits.

"One of our friends lit a joint and passed it around. I had a puff," he said.

On previous occasions, "when the joint went around the room, I usually passed it around to the next person," he added. But "sometimes throughout my life, I've had a pull on it."

"Sometimes, I guess, I have gotten a buzz, but other times no. I'm not really crazy about it."

Trudeau was elected to parliament in 2008.

Earlier this year he was picked to lead and resurrect a party that held power for most of the last century but was relegated to the margins as the country's number three political force in the last election.

Polls now put Trudeau ahead of Conservative Prime Minister Stephen Harper and if the numbers hold until the next election, expected in 2015, the young Trudeau and his Liberals could form Canada's next government.

A self-described teetotaller, Trudeau has reportedly never smoked cigarettes and doesn't drink coffee.

He told the Huffington Post that he also once tried to smoke hashish at an Amsterdam caf?? but called it a "total disaster," and suspects friends may have slipped hallucinogenic mushrooms into his spaghetti once.

Trudeau also revealed in the interview that his late brother, Michel, was facing marijuana possession charges for a "tiny amount" of pot before his death in an avalanche in 1998 and that the experience influenced his decision to call for legalizing and regulating cannabis in hopes of eliminating criminal control of the pot trade and limiting teenagers' access to it.

"I'm not someone who is particularly interested in altered states, but I certainly won't judge someone else for it," Trudeau said. "I think that the prohibition that is currently on marijuana is unjustified."

Main opposition New Democratic Party leader Thomas Mulcair told the Huffington Post that he also has smoked pot but refused to say when. The prime minister's office said Harper's asthma prevented him from ever trying cannabis.

Canadian police chiefs earlier this week urged a legislative change that would allow them to hand out fines for small amounts of pot possession instead of laying criminal charges, in order to reduce policing and court costs, and to do away with such convictions affecting Canadians' travel, employment and citizenship.

An estimated one million Canadians regularly smoke marijuana, according to the latest surveys.