A visitor looks at a display of miniature Boeing passenger aircraft at an aviation expo in Beijing. [Photo/Agencies]

SEATTLE -- A group of Chinese companies signed here Tuesday a deal with US plane maker Boeing to buy 300 Boeing aircraft.

The deal, signed by China Aviation Supplies Holding Company, ICBC Financial Leasing Co Ltd and China Development Bank Leasing with Boeing, was reached during Chinese President Xi Jinping's first state visit to the United States which was kicked off on Tuesday morning.

Meanwhile, Commercial Aircraft Corporation of China Ltd also signed a cooperative document with Boeing to build a 737 aircraft completion center in China.

The National Development and Reform Commission (NDRC) of China inked a Memorandum of Understanding (MOU) with the US plane maker on the promotion of comprehensive strategic cooperation in the civil aviation industry.