TORONTO -- Premier Doug Ford welcomed the launch of COVID-19 vaccine certificates in Ontario, saying the system is essential to prevent the province from entering into another lockdown.

The premier made the remarks at a news conference on Wednesday morning, just hours after the vaccine certificate system came into effect, noting the certificates are a temporary, but vital new measure to combat the disease.

Ontario's new vaccine certificate system requires patrons at dine-in restaurants, nightclubs, cinemas, gyms, sports facilities and other venues to present a receipt of full vaccination along with government identification before entering.

“These certificates, they're the best chance we have to get through these coming months without having to move backwards,” Ford told reporters on Wednesday.

“But, let me be very clear, this is a temporary and exceptional measure. We will only use these certificates for as long as they are needed and not one day longer.”

In Ontario, more than 85 per cent of people aged 12 and up have at least one dose of a COVID-19 vaccine in the province, and about 79 per cent of the eligible population have both doses.

Ford admitted that he was hesitant about implementing the certificate measure, but he added that health experts and the province’s medical officer of health convinced him the step was necessary.

“It's no secret that I was reluctant to use this tool, but our highest concern, what keeps me up at night, is ensuring we never lose our hard fought progress,” he said.

“We can't afford to shut down again, or experience a sudden surge in cases like we're seeing in other provinces across the country.”

The province said people with medical exemptions could use doctor’s notes to avoid the new rules. Businesses that don't comply with the certificate program and patrons who give false information may be fined.

“It's important that each of us remain patient, especially with business owners and frontline workers who are implementing the vaccine certificate,” Ford said.

“As we begin this vaccine certificate, there'll be a period of learning. I want to be clear, enforcement will lead with education and will be reasonable to business owners.”

The province’s online web portal where proof of vaccination certificates are obtained and vaccine appointments are scheduled was down earlier this morning for a previously scheduled maintenance, which occurs almost weekly.

The province says the website is usually unavailable each week for maintenance from 11 p.m. on Tuesday to 8 a.m. on Wednesday and from 11 p.m. on Saturday to 9 a.m. on Sunday.