Yemen's Iran-backed Houthi rebels seized Yemen's historic port city of Mokha on Thursday, four Yemeni government military sources said, gaining greater leverage over the Bab el-Mandeb Strait, a vital global shipping route.

The Houthis are launching attacks ⁠on the strategic Red Sea islands of Hanish, the government sources told ⁠Reuters. Government forces and their allies are relocating south to Dhubab, which sits directly on the strait, across from the island of Perim.

Control of Dhubab and the island is key to gaining hold of the strait, they said.

There has been an escalation in fighting between Saudi Arabia's Yemeni allies ​in the internationally backed government and the Houthis in recent days, creating a second theater of war in the ​Iran ⁠conflict that threatens global energy supplies.

A U.N.-brokered truce in Yemen in 2022 largely halted years of war but has not led to a lasting settlement, with the latest fighting threatening a return to full-scale war.