The United States is reportedly considering blocking the sale of engines for Comac’s C919 narrowbody programme.

Citing unnamed sources close to the matter, Reuters and the Wall Street Journal reported over the weekend that potential restrictions covering CFM International Leap-1C engines for the programme might be accompanied by limits on the export of other systems, such as Honeywell flight-control systems.

The US government will reportedly discuss the matter – as part of a larger discussion on how to restrict US technology exports to China – this week and later in the month, before arriving at a decision. The restriction would apparently take the form of a refusal to reapprove GE Aviation’s export licences for the engine. The enginemaker has obtained export licences from the US government for the Leap-1C engines since 2014, having most recently received one in March 2019.

CFM is a joint venture between GE and France’s Safran. Apart from powering the C919, other variants of the Leap are also an option for the Airbus A320neo, and the exclusive powerplant for the grounded Boeing 737 Max.

Responding to FlightGlobal’s request for comment, GE says: ”GE has provided products and services in the global marketplace for decades. We aggressively protect and defend our intellectual property and work closely with the US government to fulfill our responsibilities and shared security and economic interests.”

Honeywell declined to comment, while Comac did not respond.

Comac has six C919 test aircraft flying, all fitted with the Leap-1C. It has more than 300 Leap-powered aircraft in its order book. Comac is looking at a 2021-2022 date for the C919’s service entry.

Apart from CFM engines, the C919 will also be fitted with Chinese-made powerplants.

Progress on the developmental CJ-1000AX high-bypass turbofan, manufactured by AECC Commercial Aircraft Engine, is still unclear. It was reported in 2018 that the CJ-1000AX demonstrator engine achieved power-on. Chinese media reports indicate the CJ-1000AX is looking to enter service in 2021.

Any restriction of Leap engines to China could deal a blow to the C919, pushing its timeline further to the right. It would also mark the latest event in a simmering back-and-forth between the Chinese and US governments over trade and technology transfer.

UPDATE: Story is updated with comments from GE.