The U.N. envoy for Yemen said Tuesday he met with Houthi negotiators over the weekend in efforts to avert further escalation in Yemen amid fierce battles on the country's western coast between the Iran-backed Houthis and the Saudi-supported, but fragmented, government forces.

The renewed violence, which has killed hundreds and displaced tens of thousands, is the latest twist in Yemen's conflict, which began in 2014 when the Iran-backed rebels took over the capital, Sanaa, forcing the country's government to settle into exile in Saudi Arabia. The kingdom entered the war a year later with a multinational coalition.