Transport Canada is re-examining the validation it gave Boeing Co’s 737 MAX jets, following reports of a U.S. probe into the aircraft’s certification by the Federal Aviation Administration (FAA), Canada’s transport minister said on Monday.

Marc Garneau told reporters in Ottawa that Transport Canada might not take any action but he thought it would be wise to re-examine the validation of the 737 MAX 8 jet, which has been grounded worldwide for safety concerns following the recent crash of an Ethiopian plane of that model, which killed 157 people.

The disaster followed a Lion Air crash in Indonesia in October involving the same model plane, which killed 189 people.

Canada accepted the FAA’s March 2017 certification of the MAX under a deal where such approvals by the United States are accepted by Canada and vice versa.

“We may not change anything but we’ve decided it’s a good idea for us to review the validation of the type certificate that was given for the MAX 8,” Garneau said.

Garneau added that Transport Canada would do its own certification of a software change being prepared by Boeing within the next few weeks “even if it’s certified by the FAA.”

The FAA declined to comment.

Citing people familiar with the inquiry, the Wall Street Journal reported on Sunday that U.S. Department of Transportation officials were scrutinizing the FAA approval of MAX jets and that a grand jury in Washington subpoenaed at least one person involved in developing the MAX.

In addition, the Seattle Times reported that Boeing’s safety analysis of a new flight control system on MAX jets, known as MCAS, had several crucial flaws, including understating the power of the system.