New Delhi, Sept. 15 -- The Yemeni government vowed to send more forces to the Red Sea coast and one official conceded a "painful" defeat last week when Houthis captured the port city of Mokha and an island on the Bab el-Mandeb Strait, a crucial shipping alternative to the Strait of Hormuz.

The escalation - especially Houthi attacks on Saudi oil infrastructure and its shipping in the Red Sea - adds pressure on global oil supplies and prices, and that could give Iran leverage in its war with the United States.

As Yemen risks descending into another civil war, the United Nations estimated that more than 80,000 people in the impoverished country have been displaced by the fighting since the start of September.

One woman said a mortar shell...