Australia's biggest coal mine, the $16.5 billion Carmichael Coal and Rail Project in Queensland's Galilee Basin, has been given federal approval.

Federal Environment Minister Greg Hunt said the project proposed by Indian company Adani could go ahead, subject to 36 "strict" conditions focused on conserving groundwater.

The mine project west of Rockhampton would be one of the biggest in the world, covering 200 square kilometres and producing about 60 million tonnes of coal a year.

The colossal proposal consisted of six open-cut pits and up to five underground mines, to supply Indian power plants with enough coal to generate electricity for up to 100 million people.

China is planning the construction of two railway lines in Tibet that will extend up to the border with India and are expected to be completed by 2020, State media reported on Thursday.

The railway lines will run from the town of Shigatse, which next month will be connected to the Qinghai-Tibet railway line that extends to Lhasa. Traffic on the 254 km Lhasa-Shigatse line, which began to be built in 2010, will commence next month.

A top official of the Tibet Autonomous Region government said the railway line will be further extended during the 13th five year plan period (2016-2020), running to two regions near the border with India: Yatung, a trade centre close to Sikkim and Bhutan, and to Nyingchi in the east, near the Arunachal Pradesh border.

A third railway line will be build to Gyirong, where there is a trade and border checkpoint connecting Tibet’s Yatung county and Nepal.