Clashes between Yemen's Houthis and Saudi-backed government forces have killed 81, military and medical sources said on Friday, as the Iran-backed rebels push towards territory bordering a chokepoint in the strategic Red Sea.

Fighting erupted on Thursday, after the Houthis launched a ground assault along with rocket and drone attacks near coastal areas, vying for control of the narrow Bab al-Mandab strait at the Red Sea's southern entrance.