Canada is the only G7 country due to receive vaccines in early deliveries from the COVAX scheme.
COVAX is focused on poorer countries, and most rich nations are buying in vaccines separately.
Canada has had a rocky roll-out, and countered critics by saying its 'top priority' is vaccinating Canadians.
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Canada is not backing down after being criticized for taking a share of vaccines from the COVAX program, which distributes vaccines to poorer countries.
COVAX pools funding from richer countries for vaccines to be distributed around the world, including to poorer countries, many of which have not yet been able to vaccinate anybody.
The plan for the first round of distribution of these vaccines was announced on Wednesday, including Canada's allocation.
COVAX plans to deliver over 330 million doses of AstraZeneca/Oxford and Pfizer vaccines in the first half of 2021.
The vaccines are due to be shared out between 145 nations, including 92 low- and middle-income countries. That number of doses is enough to cover around 3.3% of the population in those countries.
As of Friday, Canada had already vaccinated around 2.7% of its population, according to figures from Our World in Data.
That pace is far ahead of most COVAX recipients, but is behind countries with similar national wealth to Canada, including the US, UK, and most of the EU.
COVAX ultimately aims to provide doses for at least 20% of the populations in recipient countries, but supply issues mean it will take many months to deliver on that promise, and richer nations are all but guaranteed to hit that level far sooner.
Other richer countries, like New Zealand, will also be getting vaccines from COVAX. But Canada is the only G7 member is listed to receive vaccine from COVAX in this first round of vaccine distribution.
Canada is forecast to receive 1.9 million doses of the AstraZeneca/Oxford vaccine in total.
Speaking to Canadian network CBC News on Wednesday, Karina Gould, Canada's minister of international development, defended the move.
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She said that Canada has contributed $440 million to COVAX, and that half of it was earmarked for buying doses for Canadians. The other half of the money was for low- and middle-income countries, she said.
"This was part of the strategy from the get-go", she said. "Our top priority is to ensure Canadians have access to vaccines."
The move comes after concerns have been raised about "vaccine nationalism", whereby richer countries are hoarding the vaccines, while poorer countries scramble to get their own stocks.
On Tuesday, President Joe Biden's administration said the US would join COVAX, though the scope of its contribution was unclear.
Oxfam criticized Canada's decision to draw on early COVAX vaccines, which it said was motivated by political pressures at home. Canada has faced some troubles with accessing vaccines quickly, despite having ordered 40 million doses of the Moderna vaccine and the 76 million doses of the Pfizer one.
Dr Jason Nickerson, a humanitarian affairs advisor with Doctors Without Borders, told Yahoo! on Wednesday that Canada was "jumping the line."
He said the effect of its decision is that low-risk people in Canada will get vaccines before high-risk people elsewhere, a situation he called "frankly indefensible."