Construction work has started on the 314m high Shuangjiankou dam, China’s Environmental Ministry has announced.

The dam, located on a tributary of the Yangtze river, is expected to be the world’s tallest once complete, the ministry said, surpassing the 305m Jinping-I dam, also in China.

Work is expected to be complete in 2022, with the project budgeted for around US$5.8 billion.