New Boeing 737 MAX's tests flights halted over engine issue
The move comes just days ahead of the aircraft's first scheduled delivery to a customer.
However, Boeing said it will stick to the MAX's delivery-schedules this month and continue the plane's production.
India's SpiceJet is among the airlines which has placed orders for the 737 MAX.
Boeing halts test flight of new 737 MAX
Why has Boeing halted testing?
Last week, Boeing received a notification of a possible issue regarding turbine engine discs made by a supplier to CFM International, which is making the 737 MAX fleet.
Boeing said, in over 2,000 hours of testing, it hadn't experienced any disc-related problems.
"Out of an abundance of caution, we decided to temporarily suspend MAX flights," Boeing said.
737 MAX is a more fuel efficient replacement of 737
The 737 MAX replaces Boeing's previous bestseller, the 737, and is designed to maximize fuel efficiency.
The 737 MAX 8 was the plane's first version and has a list price of $110 million.
The upgraded 737 MAX 9 has more seating capacity. It successfully completed its maiden flight last month.
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