A major Chinese airline may delay the delivery of an order of Boeing 737 Max jets to do extra safety inspections amid the door plug blowout saga

• China suspended deliveries of Boeing jets after the 737 Max was grounded in 2019.
• Relations appeared to be getting better after a Dreamliner was delivered last month.

Concerns around the Boeing 737 Max are obstructing the resumption of its deliveries to China, The Wall Street Journal reported.

China Southern Airlines has been preparing to receive 737 Max jets as early as this month — but is now planning additional safety inspections, according to the Journal.

People briefed on the matter also told the WSJ that China's aviation regulator has instructed airlines to conduct precautionary safety checks on their Boeing 737 Max fleets.

No Chinese airline currently operates a 737 Max 9, and the Journal reports China Southern Airlines' awaited delivery isn't the same variant as Alaska's Max 9 — which features a plug door covering a deactivated emergency exit.

The plug door blew off in midair during Flight 1282 on January 5, leading to the Federal Aviation Administration grounding all Max 9 jets with a plug door and launching a formal investigation into Boeing.

Alaska Airlines and United Airlines, the two biggest operators of the 737 Max 9, have canceled hundreds of flights as a result. But the fallout now appears to be expanding.

Boeing predicts that China will account for 20% of the world's plane deliveries over the next 20 years, so resuming business is pivotal.

China froze deliveries of most Boeing aircraft in 2019 after the 737 Max was grounded worldwide following two crashes in which 346 people were killed.

The 737 Max returned to service for most countries in 2020 after Boeing updated the MCAS software which malfunctioned in the crashes. But Chinese airlines didn't fly them again until last January.

And it wasn't until last December that a Chinese airline took delivery of another Boeing 787 Dreamliner, per Reuters.

Boeing predicts that the market for narrowbody jets like the 737 Max will be more demanding, accounting for three-quarters of deliveries until 2042.

Boeing and China Southern Airlines did not immediately respond to requests for comment.