Manitoba's finance minister says he's feeling rushed by the Trudeau government's July 2018 timeline for legalizing recreational marijuana, and he wants an extension.

Cameron Friesen says with the clock ticking there are still many unanswered questions on issues like public safety, enforcement and finding legal supplies of marijuana.

He says provinces are responsible for much of the work and the high costs needed to create a regulated cannabis market.

Friesen was speaking in Ottawa before a federal-provincial finance ministers meeting, which is exploring the issue of how to tax Canada's forthcoming legal pot industry, among other things.

He says he mentioned the idea of an extension to federal Finance Minister Bill Morneau -- but didn't reveal how much extra time he's hoping for.

Provincial ministers are planning to push Ottawa to ensure they receive a share of pot-related tax revenue that fairly reflects the added costs provinces will have to assume on the road to legalization.

Quebec Finance Minister Carlos Leitao said provincial leaders must get a fair share of tax revenue given they are shouldering the costs of putting in place infrastructure for the new industry. 

"We want to have equitable sharing of tax revenue, whatever that revenue is," he said. "We're not there yet in terms of having very precise discussions on prices and on rates of taxation. We want to make sure whatever system is put in place is equitably distributed among the provinces."