The airline's board have agreed to buy or lease eight Airbus A321neo and five Airbus A350-900 aircraft, according to two company announcements.

China Airlines said the five A350-900s -- used for long-haul flights -- could be leased for a total of US$1.148 billion or bought for up to US$1.965 billion.

The investment is aimed at supporting the airline's "long-term operational development and enhancing the flexibility and competitiveness in its global presence", it said.

The eight short- to medium-haul A321s will help to meet "operational needs", it added.

Five of them -- valued at US$240 million -- will be leased from the Air Lease Corporation for 10 to nearly 12 years. The remaining three A321s are still being negotiated.

The airline also ordered 14 Boeing aircraft in May, with the option to buy another nine planes, after China backed out of a deal to buy Boeing planes due to US tariffs on Chinese products.