Liberal Leader Justin Trudeau says legalizing marijuana is the only way to keep the drug out of the hands of children, and while the comments repeat similar statements from earlier this year, they made headlines across the country Thursday and provoked a strong rebuke from the Conservatives.

At a rally in Kelowna, B.C., on Sunday, Trudeau said he is no longer in favour of just decriminalizing cannabis.

“I’m actually in favour of legalizing it; tax and regulate it,” Trudeau said to cheers from the crowd. “It’s one of the only ways to keep it out of the hands of our kids, because the current war on drugs, the current model, is not working. We have to use evidence and science to make sure that we’re moving forward on that.”

On Thursday, Trudeau repeated the sentiment to reporters at an event in Vancouver, according to the Globe and Mail, saying that he has “evolved in my own thinking,” after reading the latest research on the topic.

Later Thursday, Trudeau reiterated his position on Twitter.

“Liberals across Canada came together to support legalizing marijuana in 2012 because the status quo is unsafe and costly. #cdnpoli," Trudeau tweeted, referring to a resolution passed at the Liberal convention in January 2012.

It remains unclear whether legalizing marijuana will be part of the Liberals’ platform for the 2015 election.

The MP for the Quebec riding of Papineau had previously said he only supported decriminalizing pot. But Trudeau told an audience at the University of Western Ontario in February that he supports legalizing marijuana to make it harder for young people to obtain while putting more tax revenue into government coffers.

When this week’s comments made headlines Thursday, Gerald Butts, who was part of the team that ran Trudeau’s campaign for the federal Liberal leadership, tweeted a link to Trudeau’s February comments.

“Must be a slow news day. @JustinTrudeau announced support for legalization months ago,” Butts tweeted.

But Trudeau’s position spurred Employment Minister Jason Kenney to tweet Thursday: “Just got email from head of adolescent drug treatment centre furious w/ Justin Trudeau for demanding marijuana legalization. #irresponsible."

In a statement Thursday, the Conservatives said “our government has no interesting in seeing marijuana legalized or made more easily available to youth.”

Dana Larsen, director of Sensible BC, a campaign for a referendum on decriminalizing marijuana in the province, said while he believes Trudeau is sincere, he will have “challenges making all those promises come true” should he become prime minister.

“Unfortunately, (politicians) tend to make those comments when they’re a long way from being to do anything about it,” Larsen told CTV News Channel in an interview from Vancouver.

Larsen said about 7 in 10 British Columbians support legalizing marijuana for a variety of reasons, ranging from the protection of civil liberties to keeping people convicted of minor drug offences from overcrowding jails. But tax revenue is also a compelling reason, he said.

“The marijuana industry is one of British Columbia’s strongest economic engines,” he said, noting that it generates about $6 billion, on par with industries such as forestry and tourism.