Toronto's top public health official says the new restrictions announced by the province will put the city in a position to challenge the resurgence of new  COVID-19 infections.

During the city's COVID-19 briefing, Dr. Eileen de Villa said the measures that will be imposed are necessary and allow the city the opportunity to reverse and lower its infection rates.

Toronto Public Health reported 350 new COVID-19 cases on Friday, bringing the cumulative total to 21,919.

De Villa noted that nearly 2,000 infections were recorded in Toronto during the first eight days of this month alone. That's 10 per cent of all the cases since the beginning of the pandemic.

"This is an important day for Toronto," de Villa said.

"If we think of COVID-19, like a forest fire, the announcement today by the provincial government is a firebreak."

Beginning on Saturday at 12:01 a.m., gyms, movie theatres, and indoor dining at restaurants in Toronto, Ottawa, and Peel Region will be shut down for 28 days.

(FULL LIST: Businesses and services impacted by new restrictions)

"I can't stress enough how difficult and painful it was to make this decision. My heart just breaks for these folks and I understand what this decision means to each and every one of you," Premier Doug Ford said during a news conference.

The new measures come a week after De Villa penned an open letter to provincial health officials, proposing to ban indoor dining and suspend fitness classes and sports activities to curb the spread of the disease.

De Villa said these actions will reduce mixing in gatherings and closed indoor spaces, which will rob the virus's chance to spread easier.

"We cannot forget (COVID-19) is always ready to erupt if we let our guard down in our daily lives," de Villa said.

"It is likely there will still be several weeks of sobering news to come."

Mayor John Tory said he supports the premier and these new measures, saying that the 28-day pause is needed to stop COVID-19.

"The progress we have made the past eight months is at incredible risk. We have to confront this resurgence aggressively," he said.

De Villa said the results of these changes will not immediately reflect on the numbers.

"Lower infection rates won't happen overnight. So, the infection rates still to come over the next few weeks will require faith that we are on the right path," she said.

"This is not the moment to breathe a sigh of relief, but rather the time to take a deep breath before we make up our minds to do what that takes."

The doctor also repeated her public plea to only celebrate Thanksgiving with those they live with and to only go out for essential trips.

She urged many to connect virtually than in-person to their extended family and friends.

"I am sorry that I have to ask it," the doctor said. "I hope it's some consolation that what we have to do this weekend should give us something to be really thankful for this time next year."