BEIJING, Oct. 31 -- China's top economic planning agency has approved plans to build three rail lines, at a cost of about 250 billion yuan (40 billion U.S. dollars).

The longest line, costing about 20 billion yuan, will carry coal more than 1,800 km from the city of Ordos in north China's Inner Mongolia to Ji'an in the eastern province of Jiangxi, according to the National Development and Reform Commission. Construction will take about five years.

The two other projects are a 137 km passenger line linking Datong in north China's Shanxi Province with Zhangjiakou in neighboring Hebei, and a 402 km linking between Xigaze and Nyingchi in southwest China's Tibet Autonomous Region.

Policymakers have been accelerating investment in infrastructure to stabilize growth in recent months.