The directive, delivered in a series of posts on his social media platform, marks a sharp escalation in the administration’s rhetoric against the energy sector.

In his posts, the president said customers are being “gouged” by oil companies and called for federal prosecutors to examine whether the industry has engaged in illegal pricing practices. The announcement did not specify which companies would be targeted or provide evidence to support the allegation of price manipulation.

The order lands as gasoline prices remain a potent political issue, with the national average for a gallon of regular fuel hovering near levels that have strained household budgets across the country. The president has frequently blamed energy producers for the costs, though industry groups have pointed to global supply constraints and refining capacity as the primary drivers.

The Justice Department declined to comment on the directive, and it remained unclear whether Attorney General William Barr had received formal instructions to proceed. Legal experts noted that proving price gouging in a federally regulated market would require demonstrating collusion or other antitrust violations, a high legal bar.

Shares of major oil companies dipped slightly in after-hours trading following the announcement. The American Petroleum Institute, a leading trade group, issued a statement arguing that gas prices are determined by global markets, not by domestic producers, and warned that a government investigation could chill investment in domestic energy production.

The move echoes similar actions taken by past administrations during periods of high fuel costs, though such investigations have rarely resulted in major penalties. Critics of the president’s approach said the directive risked politicizing antitrust enforcement, while supporters argued it was a necessary check on corporate power.

Consumer advocacy groups welcomed the news, with some calling for a broader inquiry into the entire supply chain from extraction to the pump. The White House has not yet released a timeline for the probe or indicated whether the investigation would be limited to retail pricing or extend to upstream operations.

As the administration prepares for what is expected to be a contentious election season, the price of gasoline is likely to remain a central talking point. The president’s directive signals that he intends to keep pressure on the energy industry, even as his own policies on drilling and deregulation have been criticized by environmentalists and some economists for their long-term effects on market stability.