Alberta Premier Jason Kenney says his province will start offering the Oxford-AstraZeneca shot to those 40 and older starting on Tuesday.
He tweeted the change on Sunday night, hours after Ontario made a similar announcement.
He says more details will come in the morning.
Ontario lowers age for AstraZeneca, revises some COVID-19 lockdown measures amid public outrage
The AstraZeneca vaccine had previously only been available to those over 55.
The announcement comes amid mounting pressure to expand eligibility for the shot as the third wave of COVID-19 devastates parts of Canada.
Alberta currently has the highest rate of active COVID-19 cases in the country.
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