China's Okay Airways has committed to order up to 20 Boeing 737s, in a deal worth $1.3 billion at list prices.
The agreement comprises firm orders for 12 aircraft, comprising eight 737 Max 8s, three Max 9s and one 737-900ER, as well as eight options.
Okay Airways, based in Beijing, already operates 18 737s, Flightglobal's Fleets Analyzer shows.
The new order will make the airline the first 737 Max 9 customer in China.
Okay Airways chairman Wang Sushen says the aircraft will be "a great asset to support Okay Airways' development".
He says the carrier has six operating bases, including its main one in Tianjin, but indicates the airline is aiming to increase this to eight from 2020, including a station in Beijing.
"We are going to become the best privately-owned airline in China," says Wang.
All eight options are for the Max 8, says the airframer. Okay already has six Max 8s on order, and the new commitment, once firmed, will take its overall Max fleet to 17 jets.
Boeing's Max family is exclusively powered by the CFM International Leap-1B engine.
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