US President Donald Trump has ordered an investigation into major oil companies, including ExxonMobil, Chevron, Shell and BP, over concerns that falling crude oil prices are not being reflected in gasoline prices paid by consumers.

Speaking to reporters on Thursday, Trump said Americans should be seeing lower fuel prices at the pump following recent declines in oil prices. He argued that gasoline prices remain higher than expected and accused some energy companies of failing to pass on the benefits of cheaper crude to consumers.

Trump disclosed that the Department of Justice is examining whether oil companies and other participants in the fuel supply chain are keeping petrol prices artificially high despite lower costs.

The president’s remarks mark a rare public criticism of specific oil producers by name and signal increased scrutiny of fuel pricing practices in the United States.

Industry analysts note that pump prices are influenced by several factors beyond crude oil costs, including refining expenses, transportation costs, taxes and regional supply-demand conditions. These factors can cause retail fuel prices to fall more slowly than crude oil prices.

While consumer groups have welcomed closer oversight of fuel pricing, experts say any findings of wrongdoing would require evidence of anti-competitive behavior or unlawful market practices.

The investigation comes as fuel prices remain a major concern for American consumers and a key issue for the Trump administration.