The Houthis, a militant group in Yemen who have been threatening to open another front in the Iran war, said they had targeted two oil tankers in the Red Sea.

Minutes before the Houthi statement on Wednesday, the U.K. Maritime Trade Operations Center said the master of a tanker has reported that the ship had been struck southwest of Al Shuqaiq on the Saudi Red Sea coast. Saudi Arabia didn’t immediately comment on the attack.

The Red Sea has emerged as a vital workaround for crude exports, particularly from Saudi Arabia, amid disruptions to shipping through the Strait of Hormuz. Brent crude oil rose sharply past $95 a barrel in post-settlement trading, and U.S. oil added as much as 1.8% in early trading Thursday to trade above $88 a barrel.