Air Canada and its unionized flight attendants remained at odds on Friday, despite government pleas for both sides to return to bargaining to avert a strike that would upend travel for tens of thousands of passengers.

The prospect of a systemwide work stoppage by Air Canada's unionized flight attendants loomed large on Friday with a strike deadline just hours away, despite a government plea for the two sides to return to the bargaining table.

Air Canada said it will shut down operations by the end of the day Friday as flight attendants prepare to go on strike.