The contract covers a fleet of up to 50 Airbus A320 family aircraft.
The airline already operates a fleet of nine V2500-powered A320s on routes to the rest of south east Asia and Australia.
The International Aero Engines consortium (IAE), in which Rolls-Royce is a senior shareholder, produces the V2500. Other partners in IAE are Pratt & Whitney of the US, the Japanese Aero Engines Corporation and MTU Aero Engines of Germany.
The V2500-A5 engine is designed to power the Airbus A319, A320 and A321 as well as the A319 Corporate Jet, and features a range of thrust from 98,000N to 147,000N.