As part of the U.S. trade mission to China on the occasion of President Donald Trump's state visit to the country, Boeing and China Aviation Suppliers Holding Company (CASC) have signed an agreement for 300 aircraft with a theoretical list-price value of $37bn.

The agreement was signed by Kevin McAllister, Boeing Commercial Airplanes president and CEO, in the presence of President Trump and China President Xi Jinping.

Boeing says the deal includes orders and commitments for an unspecified combination of single-aisle and twin-aisle aircraft. Press reports say the agreement includes 260 737s and 40 787s and 777s.

This latest accord follows a 140-aircraft agreement signed with Airbus in July during a state visit to Germany by Xi Jinping.

For Boeing, it is the second mega-deal with CASC in two years, following a 300-aircraft agreement announced in September 2015.