A proposed resource tax in Australia could prompt Shell, ConocoPhillips, BG Group and Santos to merge about $70bn of gas projects in the country, targeting fuel shipments to China, Japan and South Korea.

The Australia Government’s 40% tax on profits, to start from 2012, may reduce returns from the ventures that will tap coal-seam gas in Queensland for export as liquefied natural gas (LNG), reports Bloomberg.

The world’s largest mining company BHP Billiton, Rio Tinto Group and Xstrata are reviewing their Australian projects after the government announced the tax plan on 2 May.

Santos and Origin Energy, ConocoPhillips’ partner in one of four proposed Queensland LNG ventures, have said they may delay investment decisions.