The Liberal government will reveal the legislation in the second week of April, according to the Canadian Broadcasting Corporation, putting Canada on course to become the first G7 country to fully legalise marijuana use.

Since becoming the Liberal leader in 2013, Trudeau has spoken out about the need to decriminalise and regulate recreational marijuana, arguing that it would help ensure that marijuana is kept away from children and that profits don’t end up in the hands of what he has described as “criminal elements”.

Shortly after taking power, his government signalled that legalisation remained a priority, promising to unveil legislation by spring. Medical marijuana is already legal in Canada.

The federal legislation is expected to task Ottawa with licensing producers and ensuring the safety of the marijuana supply, in keeping with the recommendations of a government-appointed taskforce. Canadians who want to grow their own marijuana will be limited to four plants per household.

It will be up to Canada’s provincial governments to decide how the drug will be sold and at what price. While the federal government will stipulate that buyers must be at least 18 years old, provinces will be able to set a higher age limit if they wish.

Given the scope of work that lies ahead for the provinces, the timeline of legalisation by mid-2018 is ambitious, a senior federal official told Canada’s Globe and Mail newspaper. A date of 2019 is more likely, the official added.

The initiative has divided opinion in Canada, where analysts have estimated the country’s cannabis industry could eventually be worth somewhere between C$5bn and C$7bn annually.

Earlier this month, Saskatchewan’s justice minister said his provincial government continues to have “grave” concerns about legalisation.

“We do support medicinal uses of marijuana, but we also know that there’s going to be some significant issues that arise as a result of legalisation from a recreational perspective … not only with respect to impaired driving but with respect to a whole host of other issues,” Gordon Wyant told a convention in the province.

Saskatchewan’s minister of labour has also voiced concerns over how legalisation would affect workplace safety.

Others worry that legalisation will put Canada on a collision path with the administration of Donald Trump. While eight US states and the District of Columbia have voted to legalise recreational marijuana, the White House has hinted that the Department of Justice will do more to enforce federal laws prohibiting recreational marijuana, raising concerns over how Canada’s approach will coexist with a potential crackdown south of the border.

Nearly 400,000 people a day cross the shared border between Canada and the US, and any thickening of the border could have economic repercussions for Canada, which last year sent three-quarters of its exports to the US.

Trudeau has stressed that in the absence of legislation, recreational marijuana remains illegal across Canada. “Until we have a framework to control and regulate marijuana, the current laws apply,” he told reporters earlier this month.

The point was underscored days later as police carried out raids on more than a dozen marijuana dispensaries across the country, laying charges of possession and trafficking on nearly 20 people.