PetroChina signed a liquefied natural gas (LNG) deal with Exxon Mobil worth US$41.1 billion over the next 20 years, the Wall Street Journal reported. Exxon will supply 2.25 million metric tons of LNG a year to PetroChina from the Gorgon gas field located off the coast of Western Australia. This is the third Australian LNG deal that PetroChina has agreed to since Septmeber 2007 and is Australia’s biggest trade deal ever, said Energy and Resources Minister Martin Ferguson. China is trying to reduce its reliance on imported oil and heavily polluting coal by using new energy sources such as LNG. The Gorgon field, which has reserves of more than 40 trillion cubic feet of gas, is being jointly developed by Exxon, Royal Dutch Shell and Chevron. Shell and Exxon each own a 25% stake in the venture while Chevron owns a 50% stake and will act as operator of the project.