The U.S. and Yemen’s Iran-aligned Houthis reported separate attacks on shipping on Tuesday as prospects for ‌ending the Iran war appeared to dim, with Tehran saying the Strait of Hormuz would remain closed unless Washington accepts its conditions.

The attacks, in the Gulf of Oman leading to the strait and at the entrance to the Red Sea – both vital chokepoints for global oil supplies – come as the war shows no signs of ending despite repeated assertions from U.S. President Donald Trump of a deal being imminent.

Oil prices gained and global shares retreated amid renewed pessimism about a quick end to the conflict. Brent crude futures climbed 1.4% to settle at $88.91 per barrel and U.S. crude rose 1.3% to $83.20.

At the southern end of the Red Sea, four crew members were killed in a suspected Houthi attack on a small cargo vessel in the ⁠Bab el-Mandeb Strait on Tuesday, Yemen’s Transport Ministry said. Two Yemeni rescuers from an anti-Houthi military group were also killed, Yemen’s Coast Guard said.

The fatalities aboard the Egyptian-owned Tihamah would be the first deaths on shipping by Yemen’s Iran-aligned Houthis since the Iran war began.

The U.S. military, meanwhile, said a U.S. Navy MH-60 helicopter fired two Hellfire missiles to disable the steering gear of a Panama-flagged cargo ship. The ship ignored repeated warnings to stop violating a naval blockade on Iranian ports, the U.S. Central Command said. Maritime sources said the ship was hit off Pakistan while sailing into the Gulf of ‌Oman.