WASHINGTON, June 24 (Xinhua) -- U.S. President Donald Trump wrote on Truth Social Wednesday that he has instructed the U.S. Department of Justice (DOJ) to look into oil companies over not lowering gasoline prices in line with falling oil prices.

"The big Oil Companies are not dropping their price at the pump commensurate with the sharply lower prices they are paying for Oil. Those prices are dropping like a rock! In other words, customers are being 'gouged,'" he said.