Canadian and European Regulators to Certify Boeing 737 Max Changes in Addition to FAA

European and Canadian regulators plan to conduct their own review of updates made to the Boeing 737 Max aircraft, the Associated Press reports, displaying a lack of trust in the U.S. Federal Aviation Administration.

Planes are certified by the country in which they’re built, and typically the standards of certification are trusted globally. Since two fatal crashes involving the Boeing 737 Max killed 346 people, however, the FAA’s certification process has come under scrutiny.

The U.S. government agency reportedly allowed Boeing to conduct its own safety assessments, resulting in an incomplete report. The U.S. Department of Transportation launched an audit of the Boeing 737 Max’s certification earlier this week, an additional review to the Department of Justice’s criminal investigation.

Regulators around the world are thus wary of any further FAA statements on the aircraft. Boeing is working on updating software that can automatically dip the plane’s nose down to avoid an aerodynamic stall in some scenarios, the AP reports. When this change is completed, U.S., Canadian, and European regulators will each conduct their own review.

“I can guarantee to you that on our side we will not allow the aircraft to fly if we have not found acceptable answers to all our questions, whatever the FAA does,” the executive director of the European regulator said, according to the AP.

Canada’s transport minister promised his agency would conduct its own certification of Boeing’s modifications, “even if it is certified by the FAA.”

Countries around the world have grounded the Boeing 737 Max airplanes. Updating its software could reportedly cost Boeing at least $500 million in addition to delaying new plane orders.