US President Donald Trump has ordered the Department of Justice to look into petrol prices, which he says aren’t falling fast enough.

“The big Oil Companies are not dropping their price at the pump commensurate with the sharply lower prices they are paying for Oil,” he said in a post on Truth Social.

“Gasoline prices better start going down a lot faster than what I’m seeing!”

He did not elaborate on the instructions given to the Department of Justice.

International oil prices have plummeted this month after the US and Iran signed an interim peace deal, resulting in an increase in traffic through the Strait of Hormuz.