China may build a third west-east gas pipeline in a bid to meet strong demand along its economically vibrant eastern seaboard, state media reported Thursday.

The pipeline will start from the western Xinjiang region and is likely to end in Fujian province in the southeast, supplying natural gas to the energy-hungry Yangtze and Pearl river deltas, the China Daily said.

A preliminary plan is expected to be published early next year, said Yang Jianhong, an official at the planning unit of China National Petroleum Corp (CNPC), the country's largest oil and gas producer, according to the report.

The project is likely to be similar in length to a 9,102-kilometre (5,650-mile) gas pipeline that CNPC started to build in February, it said.

That pipeline, which will transmit gas imported from central Asian countries like Turkmenistan to Shanghai in the east and Guangdong province in the south, has a total investment 142.2 billion yuan (20.8 billion dollars). It is expected to be completed in 2011, recent Chinese reports said.

It has been designed to transmit 30 billion cubic metres (1,050 billion cubic feet) of gas each year but that will probably grow to 40 billion cubic metres after Turkmenistan last month pledged to boost supply.

The new pipeline is likely to be more expensive because of rising costs of raw materials, according to the China Daily.

CNPC's first west-east gas pipeline, from Xinjiang was completed in 2004 and was one of the biggest energy projects in the country. Annual delivery has already reached 12 billion cubic metres.