An order from the aviation leasing unit of General Electric for the latest extended-range version of the A321neo could come at the air show, they said.

Airbus declined comment and GE officials could not immediately be reached.

Planemakers continue to notch up orders after a relatively quiet opening to the Paris Airshow, which runs from June 17-23, on Monday, with the event overshadowed by the continued grounding of the Boeing 737 MAX.

Airbus will unveil an order for its A330neo wide-body jet from Philippines carrier Cebu Air after a tough battle with Boeing, as well as at least 10 A321XLRs from the same airline, industry sources said.

The aerospace industry's biggest annual event, which alternates with Britain's Farnborough Airshow, is traditionally a slugging match between Airbus and Boeing in the $150 billion a year commercial aircraft market.

But this year Boeing is still grappling with the grounding of its top-selling 737 MAX aircraft in March after two deadly crashes, while European arch-rival Airbus is dealing with the fallout from a long-running corruption scandal.

After years of bullish demand for jets, both Boeing and Airbus already have substantial number of orders that are yet to be delivered, and are looking to preserve those orders in the face of economic weakness in many parts of the world as well as attract new business.

"Although investors have started to ask questions about the state of the upcycle, the aerospace industry remains very confident in the current state of the market," analysts at Vertical Research Partners said in a note.

After announcing no aircraft orders on Monday, Boeing could unveil orders on Tuesday including a potential deal with Air Lease Corp whose founder Steven Udvar-Hazy told reporters on Monday he would be "at Boeing tomorrow".

(Reporting by Tim Hepher; Editing by Alistair Smout)