Jan. 21 (UPI) -- Boeing's stock trading was temporarily halted Tuesday after shares fell nearly 6 percent amid reports that regulators would keep 737 Max planes grounded longer than expected.
"The agency is following a thorough, deliberate process to verify that all proposed modifications to the Boeing 737 Max meet the highest certification standards," the FAA said. "We have set no time frame for when the work will be completed."
Boeing also issued its own statement Tuesday.
"We are informing our customers and suppliers that we are currently estimating that the ungrounding of the 737 Max will begin during mid-2020," Boeing said.
The "updated estimate," takes into consideration "ongoing attempts to address known schedule risks and further developments that may arise in connection with the certification process," Boeing added. "It also accounts for the rigorous scrutiny that regulatory authorities are rightly applying at every step of their review of the 737 Max's flight control system and the Joint Operation Evaluation Board process which determines pilot training requirements."