The federal government imposed the emergency directive in the aftermath of the Germanwings plane crash in France.
"If you're carrying passengers, this is going to apply to you,'' Raitt said in a surprise announcement outside the House of Commons.
Raitt said the directive requires two members of the cabin crew — not necessarily both licensed pilots — to be on the flight deck at all times.
"All we're saying is there must be two members of the cabin crew on the flight deck at all times.''
The move comes after Air Canada and Air Transat announced similar policy changes earlier today regarding the number of people required in the cockpit. Raitt said both Air Canada and WestJet would be implementing the change immediately.
Investigators revealed today that the pilot of the airliner that crashed in the French Alps earlier this week was locked outside the cockpit.
French investigators have concluded that the co-pilot deliberately crashed the Germanwings plane, killing all 150 people on board.
Air Canada said in a statement that it would not discuss flight deck protocols and access because they involve security measures.
The airline also said that when pilots are initially hired they undergo a behavioural assessment.
They also receive recurrent medical exams every year — twice a year after the age of 60, it added.
Also on HuffPost: