Bangladesh, Sept. 11 -- Yemen's Iran-aligned Houthis on Friday reached the strategic island of Perim in the Bab el-Mandeb Strait, four Yemeni government sources told Reuters, potentially tightening their grip on one of the world's vital shipping routes.

Earlier, two sources from the Saudi-backed, internationally recognised Yemeni government said its forces had withdrawn from Perim and that the Houthis had also taken the mainland Red Sea coastal town of Dhubab, which faces the island.

If the Houthis gain full control of the Bab el-Mandeb Strait, on the opposite side of the Arabian Peninsula from the Strait of Hormuz, it could give their backer Iran a critical advantage in the war with the US, reducing supplies through a second major tran...