Customers lined up at Ontario's first brick-and-mortar cannabis stores on Monday, but fewer than half of the province's government-licensed outlets were ready to open.

The Progressive Conservative government had planned to have 25 private stores launch on April 1, but some were still working through a lengthy approval process.

Premier Doug Ford defended his government's decision to hold a lottery to determine who could apply for store licences, saying more shops would be opening soon.

"Over the next few weeks we'll get it done," he said. "If it means another week or two to get it right, let's do it."

Recreational cannabis has so far only been available for purchase legally in Ontario through a government-run website. Other provinces have long had the option to buy legal pot in stores since legalization in October.

The Alcohol and Gaming Commission, which is overseeing Ontario's vetting process, said 10 stores were given the green light to open Monday -- three in Ottawa, two in Kingston and one each in Toronto, Brampton, Burlington, London, and St. Catharines.

In Toronto, Stephanie Shamoon was the second person in line outside the Hunny Pot Cannabis Co. She said she braved the unseasonal cold from 10 p.m. Sunday to be part of a significant moment.

"It's kind of a history-in-the making kind of thing," said the 20-year-old, noting that shopping in a physical store was much easier than buying pot online. "You can come in right away, pick up what you want... you can smell it."

Hunny Gawri, owner of the sprawling store, said he got barely an hour's sleep as employees rushed to get ready for the opening.

"We have a full house in here," he said. "It's everything we could have asked for."

Although cannabis retailers across Canada have faced product shortages since legalization, Gawri said his store received everything it ordered. When asked whether he was worried about running out of product in the coming days, he said, it would depend on customer demand.

In Burlington, Art Jackes lined up at 4 a.m. at RELM Cannabis Co., which had about two dozen people waiting outside when doors opened.

Jackes, 67, who is a medicinal cannabis user, said his overall experience at the store was good but he felt the prices were too high.

"The government's not going to have any chance of dealing with the black market if they don't lower the cost," he said.

Gord Nichols, who arrived at the store at 5:30 a.m., said he lined up because he wanted to be part of an important day.

"I just wanted to wait and see what the excitement is about," he said, adding that he hoped legalization lifts some of the stigma around cannabis. "It's the end of prohibition."

Store owner David Nguyen said he was happy to be one of the few shops that were open.

"We're all here to make history," he said. "We have great educators to teach about products and we also have security to ensure that they're checking IDs."

In the nation's capital a long line formed outside Fire & Flower, located in Ottawa's tourist hub, the Byward Market.

Niki Schaap said she was at the store celebrating her first day of retirement and looking for something to help with pain management.

"I'm open to lots of things in life," she said. "I also wanted to be part of the opening of the store and the first day."

Store owner Michael Patterson said he is confident he will be able to meet customer demand.

"Everyone is coming in the door with a big smile and is leaving with an even bigger smile," he said.

In Kingston, roughly 500 to 600 customers had come through the Spiritleaf store by noon, said Darren Bondar, chief executive of the cannabis-retail chain that had partnered with the lottery winner who applied for the store licence.

Bondar said Spiritleaf was "thrilled" to work on the store but hoped the next wave of retail licensing was handled differently.

"I hope that for the next round of licences, that AGCO and OCS consult with industry. There's a lot of provinces that did it different ways, so we know what works."

Lawyer Caryma Sa'd, who specialized in cannabis cases, said there was much "disappointment" over the launch of cannabis shops in Ontario.

"The way that it rolled out with a lottery that seemed completely arbitrary, no real merit component, it's not surprising that only a handful of stores in an already artificially low number of licenses, were able to open," she said.

The Tory government had initially said there would be no cap on the number of retail pot shops. But in December, citing national supply issues, the government said it was issuing licences for just 25 stores.

Stores face escalating penalties for delays -- failing to open a store Monday results in a $12,500 draw down on a letter of credit, while not opening by the end of April means applicants risk losing their entire $50,000 letter of credit.

NDP Leader Andrea Horwath slammed the government for the delays, saying it had time to put a proper system in place last fall but failed.

"This lack of access we have today is squarely at the feet of Mr. Ford and his government," she said.

Green party Leader Mike Schreiner said the Tory plan was failing the public.

"The competition here is between organized crime and private stores," he said. "Ten stores across the province is not going to put a dent in organized crime."