BEIJING - CHINA plans to expand its urban rail system nearly fourfold in as it aims to ease traffic congestion and boost economic growth, state media said on Wednesday.

By 2015, 19 cities will have new rail systems totalling about 2,100 kilometres, the China Daily said, citing Dou Hao, deputy general manager of China International Engineering Consulting Corporation (CIECC).

The investment will be on top of the 778 kilometres of urban rail lines China currently has in 10 cities such as Beijing and Shanghai, the newspaper said.

The project will involve an investment of at least 800 billion yuan (S$169 billion), said Mr Dou, whose company has been authorised by Beijing to assess the cities' metro plans.

The paper did not identify which cities would receive the investment.

'The increase is a result of government measures to boost the economy,' said Zhou Xiaoqin, another CIECC official, adding that approval of the projects had been 'very quick'.

The move marks an expansion of a previously announced plan to build 1,700 kilometres of rail in 15 cities, and reflects growing willingness to approve infrastructure projects as a way of lifting growth during the economic crisis. -- AFP