SEATTLE, WASHINGTON — Boeing is working hard to overcome quality and development issues. After the suspension of Boeing 787 deliveries, the American aircraft manufacturer is now expected to announce another delay in the B777X program.

The certification of B777X could be pushed to 2024 and the first deliveries to 2025, according to the sources who spoke to the Reuters news agency anonymously.

On March 21, the Federal Aviation Administration (FAA) warned Boeing in a letter that existing certification schedules for the 737 MAX 10 and 777X were outdated and no longer reflect the program activity. The planemaker was targeting to obtain the airworthiness certificate of 777X from the US regulator by the end of 2023.

"We remain focused on working transparently with regulators and our customers," Boeing said in a statement last week on Friday.

The 777X is the larger version of the current 777 series with foldable wingtips. It has been in development since 2013, and the initial purpose was to introduce the jet to the widebody market in June 2020. But two fatal crashes of two brand new 737 MAXs and debates over the company's certification process of its aircraft forced the American airframer to be more cautious in the development process of new aircraft.

Boeing is also working to secure airworthiness approval for the 737 MAX 10, the larger variant of the 737 MAX family jets, by the end of the year ahead of a critical safety deadline set by American Congress.

A law issued in 2020 requires Boeing to introduce a new safety standard for cockpit alerts by December 2022, of which the deadline can be extended only by congress itself.

On the other hand, Boeing is working to resume halted 787 Dreamliner deliveries over structural flaws in the second half of 2022.