US President Donald Trump determined this Thursday that petroleum production, refining and related activities are essential to national defence, a move that could open up US funding for fossil fuel projects.

In a presidential memo, he also invoked part of the Cold War-era Defence Production Act, allowing him to provide financial incentives for oil-related activities, pipelines and storage of liquid fuels. Prices for crude oil and diesel have surged since the joint US and Israeli attack on Iran at the end of February.