A Boeing 737 Max takes part in a flying display during the 52nd Paris Air Show at Le Bourget Airport near Paris, France June 22, 2017. REUTERS/Pascal Rossignol

(Reuters) - China Southern Airlines Co Ltd 600029.SS said on Wednesday it had placed an order for 30 Boeing Co BA.N 737 MAX narrowbodies for its Xiamen Airlines subsidiary in a deal the plane maker said was worth more than $3.6 billion at list prices.

The order, including 20 737 MAX 8s and 10 737 MAX 10s for delivery between 2019 and 2022 will be used to increase efficiency and capacity, China Southern said in a filing to the Hong Kong Stock Exchange.

Xiamen Airlines in July had signed a provisional deal during the 2017 Paris Airshow to join the group of launch customers for the 737 MAX 10, the largest version of the Boeing narrowbody family.

Boeing said the firm order for 30 jets for Xiamen Airlines had been booked in 2017 and attributed to an unidentified customer at the time. The U.S. plane maker last year received 912 net orders after cancellations, while rival Airbus SE AIR.PA received 1,109.

Xiamen Airlines operates an all-Boeing fleet of more than 160 jets and the new airplanes will be used with subsidiaries including Hebei Airlines and Jiangxi Airlines, Boeing said in a statement.