PetroChina (PTR.NYSE, 0857.HKG, 601857.SH) will buy a stake in a major Australian liquified natural gas project from BHP Billiton (BHP.NYSE, BLT.LON) for US$1.63 billion, Bloomberg reported. The deal will give PetroChina a stake in two LNG projects being lead by Woodside Petroleum (WPL.ASX) in Western Australia: a 20% stake in the West Browse venture and an 8.33% stake in the East Browse joint venture. The purchase follows record Chinese oil and gas acquisitions in 2012 and gives PetroChina a share in Australian natural gas worth, by a Deutsche Bank (DB.NYSE) estimate, US$46 billion. China’s interest for oil and gas assets in the Asia-Pacific region is being driven by rapidly increasing energy demand in the country; China’s energy demand grew by double the global 2.5% average in 2011. PetroChina aims for half its oil and gas output to come from overseas by 2020.