The prospect of the most petroleum-friendly US policy settings for decades has revived worries about a potential flood of natural gas exports posing a competitive threat to Australian producers in Asia, the biggest market.

In the "America First Energy Plan" posted on the White House website shortly after Donald Trump's inauguration as US President, the new administration pledges to "embrace the shale oil and gas revolution" and take advantage of "the estimated $US50 trillion in untapped, shale, oil and natural gas reserves".