TORONTO (AP) — A lockdown and stay at home order is being extended in Canada's largest city until at least March 8.

The shutdown in Toronto began on Nov. 23 after a second novel coronavirus wave hit the province.

Ontario Health Minister Christine Elliott said it was a difficult but necessary decision.

Dr. Eileen de Villa, Toronto's medical officer of health, asked the provincial government this week to extend the lockdown, saying she has never been more worried about the future because of new coronavirus variants.

Scientists say the U.K. variant found in Ontario spreads more easily and is likely more deadly, but so far existing vaccines appear to be effective against it. Canada has had a shortage of vaccines until this week.

Schools just reopened in Toronto this week and retail stores had been scheduled to reopen Feb. 22.

The stay-home order was lifted for the majority of the province earlier this week as the government moved ahead with an economic reopening despite warnings it could set off a third wave of infections.