WASHINGTON — Air China signed an agreement Friday to buy a total 31 Boeing passenger and cargo planes from Boeing, the Chinese flag carrier said.

Air China said it would purchase 20 Boeing 737-800 aircraft, two Boeing 747-8 aircraft, one Boeing 777-300ER aircraft and eight Boeing 777 cargo planes.

The total value of the deal is $5.2 billion at current Boeing list prices.

"The Boeing Company has granted to the Company significant price concessions with regard to the Boeing Aircraft," Air China said in a statement.

The deal is subject to Chinese government approval.

Boeing spokesman Jim Proulx said Boeing would announce the order upon government approval.

"We look forward to working with Air China, a long-time valued customer, to obtain approval," he said.

Copyright Agence France-Presse, 2013