Almost 200,000 COVID-19 vaccine doses have been administered in Toronto, and more shots are being injected in the arms of residents in clinics this weekend.

In a news release, the city said a number of hospitals and community healthcare centres are operating 15 clinics on Saturday and Sunday to vaccinate those in Phase 1 priority groups, including residents aged 80 years and older, who have a confirmed appointment.

"The city of Toronto, Toronto Public Health, hospitals and community healthcare centres are all working together to get Torontonians vaccinated as quickly as possible. Getting vaccinated protects individuals, their close contacts and the community," the release stated.

The city said 197,155 vaccine doses have been administered so far.

Earlier this week, Toronto officials responded to criticism that the city is falling behind other regions in vaccinating people over the age of 80.

The city said it had administered COVID-19 vaccines to seniors in hospitals and congregate settings, but wider availability of vaccines for residents above the age of 80 will only occur when supply improves, and the provincial booking system launches on March 15.

The province released an update on its vaccination plan on Friday, announcing who will be prioritized in the second phase of its rollout set to run from April to July.

On the same day, Health Canada authorized the country's fourth COVID-19 vaccine, the single-dose Johnson and Johnson shot.

Retired general Rick Hillier, the head of the province's vaccine task force, said there had been a “seismic shift” in the province's vaccination rollout following the approval of two more vaccines, supply ramping up, and new guidance on the extension of interval between two doses.

"I want to say by the first day of summer we want to have, vaccine supply dependent, we want to have a first needle in the arms of every person in Ontario who is eligible for the vaccine and wants to get," he said during a news conference on Friday.

More than 860,000 doses have been administered and over 270,000 people have been fully vaccinated in Ontario so far.