Stephen Harper says a majority of Canadians agree with his opposition to legalizing marijuana, proving he's not behind the times on the way forward on pot.

A government opinion poll released one year ago found that more than two-thirds of Canadians wanted the federal government to ease the laws around possession and use of cannabis, with about 14 per cent saying the laws should stay the same.

But Harper says changing those laws would reverse what he calls a decline in marijuana usage in Canada.

He says in jurisdictions where marijuana is legal, such as parts of the U.S. and Europe, the drug becomes "more readily available to children, more people become addicted," and there is a decline in health outcomes.

The tough-on-drugs message is one the Conservatives have been using for months to drive a wedge between Harper and his opponents -- most particularly the Liberals and leader Justin Trudeau.

The Conservatives promised today that, if re-elected, they would spend almost $27 million a year to help the RCMP root out drug labs and change the focus of the national mental health commission that it created in 2007.

The campaign pledge would see an extra $4.5 million per year, on top of the $22 million currently budgeted, for an RCMP team designed to crack down on illegal drug labs and marijuana grow-ops.

The party also wants to spend $500,000 a year over four years on a national toll-free hotline for parents to call to get information about drug use among the country's youth.

Harper will be travelling to Vancouver later on Tuesday, landing in the city with Canada's first supervised injection site.

Harper argues such sites "pull the entire drug trade" into communities.