Three subway lines will reach a planned new airport in southern Beijing's Daxing district, Chinese media reported.

The capital will begin construction on its second airport next year to ease the burden of Capital International Airport.

Plans for the new airport was displayed during a sci-tech expo late last month, showing three subway lines connecting with the terminal.

The new airport is estimated to cost at least 70 billion yuan ($11.3 billion) and is to be completed by 2017.

Beijing is the only one among the world's major cities with just one airport. London has five airports; Paris has three, and Tokyo also has two.