The world's longest cable-stayed bridge has officially opened in eastern China, linking the two banks of the Yangtze river, state media reported Tuesday.

The Sutong bridge, which spans 1088 metres over China's longest waterway and links the cities of Suzhou and Nantong, officially opened with a ceremony on Monday after a month-long trial, the Shanghai Daily reported.

The six-lane bridge is expected to boost economic growth in the region and cut the travel time between Shanghai and Nantong to one hour from the previous four hours, the report said.

Up to 30 000 vehicles a day crossed the bridge during the trial, the Xinhua news agency reported.

"With the bridge, it takes just seven minutes to drive across the Yangtze," the agency quoted Jiangsu province's transportation director, You Qingzhong, as saying.

The $1.15-billion bridge, which overtakes Japan's 890-metre Tatara Bridge as the longest of its kind, is a feat of modern Chinese engineering, the project's chief engineer Wu Shouchang said.

"The bridge is a good demonstration of China's scientific achievements in bridge construction over the past years," Xinhua quoted Wu as saying.

The bridge, 108 kilometres upstream from the mouth of the Yangtze River, joins the national highway network on both banks, Xinhua said.

The bridge is supported by soaring steel and concrete towers that stand 300 metres tall.

AFP