TIANJIN, -- China has approved a plan for expanded customs service and international trade in the northern major port of Tianjin, the world's fourth-largest harbor by cargo throughput.

Under the plan, the water area of Tianjin Port open to the world will increase by 1,120 sq km to reach 1,590 sq km, said an official of the Port Service Office of the Tianjin municipal government on Sunday.

It also includes construction of 71 new berths, raising the total number of berths to 146. The expansion will serve Tianjin's goal of building an international port city.

"To achieve effective and convenient opening up, coordination is needed between government departments and port authorities in customs services," the official told Xinhua.

The largest comprehensive port in north China, the Tianjin Port has established trade ties with more than 500 ports in 180 countries and regions around the world.

The port's cargo throughput exceeded 500 million tonnes in 2013. Located on the coast of the Bohai Sea, the Tianjin Port is exceeded only by the Ningbo-Zhoushan Port and the Port of Shanghai in east China and the Port of Singapore in terms of cargo throughput volume.

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