Boeing 737 MAX planes still fail to get the nod of the Federal Aviation Administration (FAA) to resume operation, given the extended time for fixing software problems and completing other steps.

Several government and industry officials said that Boeing still needs to respond to all the safety concerns raised by U.S. regulators. Boeing 737 MAX is now expected to be operating again by January 2020, the Wall Street Journal reported Sunday.

Boeing leaders and international aviation regulators have been analyzing issues covering emergency recovery procedures and some suspect electronic components. Some of those assessments are further complicated because they also include earlier 737 models, according to the Wall Street Journal.

Meanwhile, the American Airlines Group said Sunday that it will keep the MAX planes off its schedule until this November, which is two months longer than it had planned.

"American Airlines remains confident that impending software updates to the Boeing 737 MAX, along with the new training elements Boeing is developing in coordination with our union partners, will lead to recertification of the aircraft this year," the airline said in a statement on Sunday.

The two fatal 737 Max aircraft crashes that killed a total of 346 people triggered the global grounding of the aircraft, resulting in a 37-percent drop in deliveries for the first half of the year.

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