British group Rolls-Royce says it has won a large chunk of a multi-billion-dollar engine order from Jetstar Airways, the discount carrier offshoot of Qantas.

‘Rolls-Royce, the global power systems company, has won a share of an order from Jetstar Airways for V2500 engines to power up to 90 Airbus A320 family aircraft,’ the London-listed company said in a statement on Thursday.

‘The order is worth up to $US1.2 billion ($A1.34 billion) to Rolls-Royce if all options are exercised.’

It added: ‘The contract includes a long-term engine service agreement for these aircraft as well as engines installed on 40 aircraft already operated by the three Jetstar Group airline brand businesses.’

Earlier in Sydney, Jetstar had announced that it had entered a $US3.5 billion ($A3.92 billion) deal with the International Aero Engines (IAE) consortium to supply low-emissions engines for its new A320 Airbus fleet.

The V2500 engine is made by the Swiss-based IAE consortium, of which Rolls-Royce is a senior shareholder.

The other partner firms are Pratt Whitney, the Japanese Aero Engines Corporation and MTU Aero Engines.

Jetstar said on Thursday that it would use the V2500 engine to power a new fleet of 50 A320 aircraft, with options and purchase rights on up to 40 more planes.

The new planes would be used on Jetstar’s Australian and New Zealand routes, as well as for flights operated by Singapore-based subsidiary Jetstar Asia/Valuair, it added.

Jetstar CEO Bruce Buchanan said the green, cost-saving deal included $US2 billion ($A2.24 billion) in servicing, repair and replacement coverage for the new engines and 40 that the airline already had in operation.