Boeing and Singapore Airlines (SIA) have announced a deal for 20 777-9s and 19 787-10s, during a ceremony at the White House.

The order, previously attributed to an “unidentified customer”, is worth $13.8 billion at current list prices.

“The value of this sales transaction will sustain thousands of US suppliers and more than 70,000 direct and indirect US jobs during the delivery period of this contract,” Boeing said.

The airline also has options for 12 additional aircraft, six of each aircraft type.

The signing ceremony, witnessed by US President Donald Trump and Prime Minister of Singapore Lee Hsien Loong, included Singapore Airlines’ CEO Goh Choon Phong and Boeing Commercial Airplanes’ President & CEO Kevin McAllister.

“SIA has been a Boeing customer for many decades and we are pleased to have finalised this major order for widebody aircraft, which will enable us to continue operating a modern and fuel-efficient fleet,” said Goh.

“These new aircraft will also provide the SIA Group with new growth opportunities, allowing us to expand our network and offer even more travel options for our customers.”

Singapore Airlines has more than 50 777s in service and is the launch customer of the 787-10, which is set to deliver in the first half of 2018. With a prior order for 30 787-10s, the airline now has 49 on order, making it the largest customer for this type. Its subsidiaries SilkAir, Scoot and SIA Cargo also operate Boeing airplanes with the 737 MAX 8 and 737-800, 787-8 and 787-9 Dreamliners and 747-400 Freighter types in service, respectively.