Oil prices climbed on Wednesday after the United States carried out fresh strikes on Iran in response to Tehran’s attacks on commercial vessels transiting the Strait of Hormuz.

US benchmark West Texas Intermediate (WTI) crude for August delivery advanced 2.1% to $71.87 per barrel, while Brent crude, the global benchmark, for September delivery gained 1.9% to $75.53 per barrel.

The US launched what it described as “powerful strikes” aimed at imposing significant costs for attacks on commercial shipping, according to the US Central Command. Explosions were reported on an island near the Strait of Hormuz, Iran’s Mehr news agency said, while Deputy Foreign Minister Kazem Gharibabadi warned that Tehran would retaliate.

In a separate move, the US Treasury revoked a sanctions waiver that had allowed Iran to export oil, reversing a key provision of the interim peace agreement with Tehran. The escalation followed attacks on three vessels in the strategic waterway, including a gas carrier and a Saudi oil tanker, making Tuesday the busiest day for such incidents since the deal took effect last month.