TORONTO -- Ontario's Progressive Conservative government says the province will require 11 million doses of the COVID-19 vaccine in July and August in order to meet Premier Doug Ford's promise of a fully vaccinated population by the end of this summer.

The pledge came after Prime Minister Trudeau said every eligible Canadian should be offered one dose of the vaccine this summer and will be fully vaccinated "by September," allowing for normal life to resume in the fall.

The premier, expressing dissatisfaction with that timeline, offered a new one instead: having Ontarians fully vaccinated by Sept 22, the official end of summer.

"If we get the supply we will work our backs off to have a two dose summer, instead of a one dose summer," Ford said on Thursday.

In order to achieve that, the government said it would require millions of additional doses during the summer months from the federal government.

"Assuming there's no supply disruptions, 11 million more vaccines to get everyone in Ontario 12 and over two doses," PC MPP David Piccini told CTVNews Toronto.

While the government didn't say when they would need to receive those doses in order to achieve that target, the province is expecting to receive nearly seven million doses of the Pfizer-BioNTech and Moderna vaccines over the next six weeks.

As additional doses arrive, members of the provincial vaccine distribution task force believe the province will start shortening the length of time between doses and rely on 24-hour clinics and pharmacies to fully vaccinate eligible Ontarians.

"I think its pretty reasonable to suggest that many people will be getting a second dose throughout the summer and shorten the four months to a little bit less for some people," said Dr. Isaac Bogoch, an infectious disease specialist with the University Health Network.

While the federal government hasn't provided exact allocations for July and August, Trudeau said the government will have enough supplies to cover the remainder of the population.

Bogoch cautions, however, that promises are difficult to keep as vaccine distribution faces variables.

"It's really hard to look anyone in the eye and tell anyone with any degree of certainty when x number of people will be vaccinated."