Boeing signaled on Thursday that it no longer expects its 737 Max jet to be certified by the end of the year and instead will work with the Federal Aviation Administration to return the plane to service in 2020.

The acknowledgment came after chief executive Dennis Muilenburg met with top officials at the FAA.

“We will work with the FAA to support their requirements and their timeline as we work to safely return the Max to service in 2020,” the company said in a statement.

In an email sent just before the meeting, the FAA said it would not be pressured into rushing the recertification process.

“The purpose of the meeting is to ensure Boeing is clear on FAA’s expectations regarding the ongoing review of the 737 MAX,” read the email sent to House and Senate committees conducting separate investigations of the circumstances surrounding two fatal crashes of 737 Max jets that have killed 346 people. “The Administrator believes it is in the interest [of] safety and the overall certification efforts of FAA and the international community that we continue to make progress while taking the time to get this right.”

The email’s language appears targeted at Boeing’s public statements over the past few months that it expected the jets to be recertified by the end of this year. The planes have been grounded worldwide since March.

“The Administrator is concerned that Boeing continues to pursue a return-to-service schedule that is not realistic due to delays that have accumulated for a variety of reasons,” the email stated. “More concerning, the Administrator wants to directly address the perception that some of Boeing’s public statements have been designed to force FAA into taking quicker action.”

“The Administrator wants to make clear that both FAA and Boeing must take the time to get this process right,” the email concluded. “Safety is our top priority and the Administrator believes public statements must reflect this priority.”

In a statement, Boeing officials characterized Thursday’s meeting as “productive.”

“Boeing reaffirmed with the FAA that safety is our top shared priority, and we committed to addressing all of the FAA’s questions as they assess MAX certification and training requirements,” wrote Boeing spokesman Gordon Johndroe.

Also on Thursday, American Airlines became the first U.S. carrier to announce it was removing the 737 Max from its schedule until April 7. The airline had previously planned to resume Max flights in March. American has 24 Max jets in its fleet.

United and Southwest airlines, which have previously said they expect to resume 737 Max service in March, have not announced changes to that schedule. However, the Southwest Airlines pilots union said in a bulletin to members that Max service would probably be delayed until at least April.

The meeting between the FAA and Boeing comes just a day after Dickson appeared before a House panel investigating whether Boeing’s rush to get the plane to market may have been a factor in the two fatal crashes of the popular jetliner and whether changes to the FAA’s process for certifying the jets were safe to fly may have also contributed.

Dickson was repeatedly pressed on what action the agency took in the wake of an internal analysis that found that “as many as 15” Max crashes could occur if changes were not made to an automated flight control system known as the Maneuvering Characteristics Augmentation System (MCAS), which was unique to the 737 Max.

For the past several months, Boeing has been working to make software fixes to that system, which has been implicated in the crashes of a Lion Air jet in October 2018 and an Ethiopian Airlines plane in March. Investigators think bad data from a single angle-of-attack vane triggered MCAS and repeatedly forced the plane’s nose down, making it impossible for pilots to regain control of the plane.

Earl Lawrence, the FAA’s executive director for aircraft certification, said “there wasn’t an additional action” because the FAA had issued a safety order and a decision had already been made to redesign the flight control feature. The report addressed “how much time would we allow Boeing to redesign this system,” Lawrence added.

Edward Pierson, a former senior manager involved in the 737 program, testified Wednesday and urged lawmakers to also examine what he believed was a “chaotic” environment at the factory where the 737 Max jets were built. He said pressure to manufacture more jets more quickly despite a shortage of parts and qualified personnel may have been a factor in the crashes. Dickson told lawmakers that he would report back on the agency’s investigation into issues at the Renton, Wash., factory.