Japan’s Transport Ministry banned 737 Max airliners from its airspace, a day after their U.S. counterparts grounded Boeing Co.’s top-selling airframe.

Citing the U.S. Federal Aviation Administration’s decision, the agency said in a statement on its website that it informed foreign airline operators of its decision. None of Japan’s carriers operates the single-aisle jet, although ANA Holdings Inc. has an order for 20 Boeing 737 Max 8 aircraft for deliveries starting in 2021, with an option on 10 more.

The archipelago is a major market for Boeing, and ANA is the biggest airline customer for the Chicago-based aircraft maker’s 787 Dreamliner. The 737 Max family is Boeing’s largest seller and accounts for almost one-third of the company’s operating profit. More than 40 nations have announced the grounding of the jet, and some cases a ban on flyovers of the plane.

Japan-bound 737 Max flights are mostly operated by Chinese companies, and those have already been grounded there.