Canada has defended its decision to draw on a supply of coronavirus vaccines from a global inoculation-sharing initiative known as Covax.
Covax pools funds from wealthier countries to help buy vaccines for themselves and low-income nations.
The scheme has announced a plan to deliver more than 330 million vaccine doses in the first half of 2021.
Canada is the only member of the G7 group of rich countries listed as a Covax beneficiary at this stage.
Other wealthier countries, including New Zealand and Singapore, have requested an early allocation as well.
Most of the first doses available, though, will be delivered to low- and middle-income countries.
Many of those countries haven't even started vaccinations. Meanwhile, Canada has vaccinated 2.29% of its population with one dose, including 48% of health workers, government data shows.
Aside from Covax, agreements for 398 million doses of vaccines have been struck by the Canadian government - more than enough to cover the country's population of 37 million.
How has Canada defended the move?
In an interview with Canadian broadcaster CBC News, International Development Minister, Karina Gould, was asked why the country decided to access Covax vaccines now.
"Our top priority is to ensure Canadians have access to vaccines," the minister said. "Covax's objective is to provide vaccines for 20% of the populations of all member states, both self-financing and those who will receive donations.
"Canada made the decision, as other countries have, to take on this first allocation, because we recognise how important it is that all Canadians have access to vaccines."
Canada is facing temporary delays for the two vaccines currently authorised in the country. That has put Mr Trudeau under pressure to ensure a timely vaccine rollout .
Canada lacks domestic production capacity for vaccines. Moderna is only delivering about 78% of the planned number of doses this week. Pfizer vaccines have also been delayed amid efforts to scale-up European production.
What is Covax and how is it distributing vaccines?
Covax works towards the development, purchase and delivery of vaccines to more than 180 countries.
It was launched in April 2020 and is led by the World Health Organization (WHO), together with the Global Vaccine Alliance and the Coalition for Epidemic Preparedness Innovations.
Covax released its first vaccine distribution forecast on Wednesday, outlining how many doses of the Pfizer-BioNTech and AstraZeneca-Oxford vaccines it expected to deliver.
The forecast said the initial batch of about 330 million doses would cover, on average, 3.3% of total populations of 145 participating countries.
The forecast illustrates the challenge of vaccinating the global population against the coronavirus, at a time when access to jabs is limited and highly unequal.
Health experts say that, unless vaccines are shared more equitably, it could be years before the coronavirus is brought under control at a global level.
How many initial Covax doses will Canada get?
Covax's forecast said an initial 1.9 million doses of the AstraZeneca vaccine will be sent to Canada.
Canada contributed $440m (£324m) to Covax in September, half of which secured doses for itself from about nine vaccines candidates.
The other half goes into a pooled fund to buy doses for 20% of the people in 92 low- and middle-income countries.
But other high-income countries with large stocks of vaccines, including the UK and Israel, were not included on Covax's distribution list.
On Wednesday, Gavi chief executive officer Seth Berkley said the group's most important role is to "supply vaccines for countries that otherwise wouldn't get access".
"Does it help when countries that have a lot of bilateral deals don't take doses?" he asked. "Of course it helps because that means there are more doses available for others."