The average price of diesel in the U.S. reached $5.69 on Wednesday, the highest since the war with Iran began in February.

The average diesel price has risen 51 percent from $3.76 as of Feb. 28, according to an NBC News report citing AAA data. Global diesel refining capacity is down because of Iranian airstrikes in facilities in the Middle East and Ukraine’s attacks on refineries in Russia, the world’s second-largest diesel exporter after the U.S.

The price increase has led to a rise in profits for refining companies, with Valero and Marathon both reporting share price increases of more than 45 percent since mid-June, according to NBC.