Beijing Daxing International Airport will be put into operation before Sept. 30, the country's top civil aviation official said Sunday.

Construction of the airport's main body is finished and inner decoration and electromechanical equipment installation and testing are underway, said Feng Zhenglin, head of the Civil Aviation Administration of China, adding that all the work will be completed by June 30.

Feng made the remarks in his capacity as a member of the 13th National Committee of the Chinese People's Political Consultative Conference, the country's top political advisory body, on the sidelines of its annual session which opened on Sunday.

The airport is ready for operation as it has completed flight checks, Feng said, adding that the airport will connect "seamlessly" with subway and high-speed railway.

The new airport sits at the junction of Beijing's southern Daxing District and Langfang, a city in Hebei Province. It is expected to handle 45 million passengers annually by 2021 and 72 million by 2025.