Crude oil prices rose sharply Friday as Iran escalated attacks in the Strait of Hormuz, Houthi militants fired missiles at Saudi Arabia and Ukraine vowed to keep striking Russian refineries.

Brent futures hit a session high of $110 per barrel for the first time since May before easing slightly to close at $109.86, a gain of 3.7%.

U.S. West Texas Intermediate rose 3.5% to settle at $101.41 per barrel. WTI added more than 10% this week while Brent advanced nearly 5%.

Saudi Arabia intercepted several missiles fired over the Red Sea on Friday, including one that was heading toward the oil export terminal Yanbu, a military spokesman said. Three drones were also destroyed in the kingdom's Riyadh and southern regions, the military said.

Iran-allied Houthi militants in Yemen have repeatedly fired at Saudi Arabia this week. Oil giant Aramco came under attack when one of its administrative buildings in Dhahran was hit Tuesday, the kingdom's energy ministry said.

The Houthis attacked Riyadh's international airport on Oct. 10, killing 12 and injuring more than 300.