Korean Air Lines Co., South Korea’s top air carrier, said Wednesday it has signed a memorandum of understanding (MOU) with Boeing Co. to buy 11 fuel-efficient aircraft as part of its efforts to modernize its fleet and better deal with environmental issues.

Korean Air said five B747-8I and six B777-300ER passenger jets will be gradually delivered from 2016 onwards if the purchase is completed through further negotiations with Boeing.

The MOU was signed between Cho Won-tae, an executive vice president of Korean Air, and Ray Conner, the president and CEO of Boeing Commercial Airplanes, at the Paris Air show on Tuesday. Cho is the only son of Korean Air Chairman Cho Yang-ho.

The carrier did neither elaborate on a specific time frame for negotiations nor the financial costs of introducing the aircraft.

The purchase will “enable Korean Air to strengthen its service competitiveness and to cope with environmental issues efficiently,” the carrier said in a statement, noting both the B747-8I and B777-300ER show 14 percent better fuel efficiency than the B747-400s.

The carrier also said it plans to dispose its 15 remaining B747-400s by 2017 and replace them with efficient cutting-edge aircraft.

“Korean Air has steadily built its reputation as an early adopter of new technology and innovation, and Boeing airplanes have played an instrumental role in that strategy,” Conner said at the MOU signing ceremony, according to Korean Air.

The carrier said the planned deal would expand its backlog for B747-8Is to 10, adding that it plans to put the planes into operation starting in 2015.

Korean Air also said it plans to introduce 64 cutting-edge aircraft by 2018, including 10 Boeing B747-8Is, 10 B787-9 Dreamliners, four Airbus A380s and 10 Bombardier CS300s.

Korean Air operates a fleet of 149 planes as of June. (Yonhap News)