The US transportation secretary announced on Wednesday afternoon that no grounded Boeing 737 Max 9 would return to service “until it is safe”, after Alaska Airlines announced the cancellation of all flights on its 737 Max 9 planes at the direction of the Federal Aviation Administration.

Pete Buttigieg said he was “not putting a timeline” on when the FAA will allow the planes to resume flights.

Every plane that the US aircraft manufacturer delivers “needs to be 100% safe”, Buttigieg added.

He said he has spoken to the head of Boeing and told him the company needs to do everything it can to establish 100% confidence in its planes.