Iran's navy said four vessels were struck simultaneously while transferring oil cargo ship-to-ship in the northern Persian Gulf and continued burning. The Islamic Revolutionary Guard Corps Navy did not say who was responsible for the strikes.

US President Donald Trump said American forces could stay in the region a bit longer, arguing recent strikes had eliminated Iran's nuclear capabilities. The remarks came amid ongoing tension between Washington and Tehran.

Brent crude held near $109 a barrel after Ukraine's drone strikes set fire to an oil terminal and depot in St. Petersburg, Russia. A separate rise in tanker attacks near the Strait of Hormuz added to global supply concerns.