An unpainted Boeing 737 MAX aircraft is seen parked in an aerial photo at Renton Municipal Airport near the Boeing Renton facility in Renton, Washington, U.S. July 1, 2019. Picture taken July 1, 2019.

Lindsey Wassen | Reuters

Boeing on Wednesday said it has paused deliveries of its 737 Max after an electrical issue grounded more than 100 of the planes worldwide earlier this month.

The problem is the latest to impact the planes, which were grounded for most of 2019 and 2020 after two fatal crashes killed 346 people. Boeing had resumed deliveries of the jets, its best-selling aircraft, late last year after regulators approved a number of fixes after the crashes.

A final fix for the planes has taken longer than originally expected and comes as airlines are gearing up for a busy summer travel season after a pandemic-devastated 2020. CEO Dave Calhoun told CNBC earlier Wednesday that he expected a fix “in relatively short order” but did not provide an exact date. The Federal Aviation Administration, which approves the fix, did not immediately comment.

A fix for the electrical issues will likely take just a few days, Calhoun said.

Calhoun said on a quarterly call that the new pause in Max deliveries to airlines “will make our April deliveries very light.”

“At this time, we expect to catch up on deliveries over the balance of the year,” he said.

Boeing shares were down more than 3% in midday trading after Boeing reported a wider-than-expected loss.

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