President Donald Trump has ordered the Justice Department to investigate oil companies that he alleges are price gouging. Photo by Samuel Corum/UPI | License Photo

June 24 (UPI) -- President Donald Trump has ordered the Justice Department to investigate oil companies that he alleges are price gouging.

Trump posted on social media Wednesday that he has directed the Justice Department to investigate, as gas prices are not falling in step with the price of oil.

"The big Oil Companies are not dropping their price at the pump commensurate with the sharply lower prices they are paying for Oil," Trump wrote. "Those prices are dropping like a rock! I have instructed the DOJ to immediately start looking into this. Gasoline prices better start going down a lot faster than what I'm seeing!"

It is not the first time the president has wielded the authority of the Justice Department against an issue affecting him politically in the eyes of consumers. He also directed an investigation into former Federal Reserve Chairman Jerome Powell because he disagreed with the central bank maintaining elevated interest rates.