Four months after recreational cannabis sales became legal in Canada, stores are running out of the product. One expert says it could take five years to get back on track.

In Quebec, shortages have forced retail outlets to operate for just three days a week. New Brunswick’s provincial retailer has laid off 60 workers due to a lack of supply. The problem could get even worse when Ontario’s first 25 brick-and-mortar stores open on April 1.

George Robinson, who runs the cannabis firm RavenQuest, told CTV News that he believes it could take five years before supply meets demand.

"We're absolutely not getting anywhere close to the (needed) supply,” he said.

Thomas Clarke, who owns a private retail store in Portugal Cove, N.L., recently ran out of supplies for two weeks. He then received a $15,000 shipment that he expected to last only a couple of days.

Clarke told CTV’s Atlantic Bureau Chief Todd Battis that black market dealers are laughing at him.

"They say ‘Ha ha, you don't got any cannabis in your store, you're only making seven-and-a-half per cent (profit) ... our business on the black market is thriving and we're making 100 per cent’,” Clarke said.

The Liberal government has long argued that legalization of recreational cannabis will reduce crime by shutting down the black market.

Despite the shortages, Minister of Border Security and Organized Crime Reduction Bill Blair said he’s confident the plan is on track.

“Many jurisdictions have made real progress,” he said. “Some clearly have a little more work to do.”