The impact of the most severe drought to hit southern Africa in 35 years is expected to worsen in the coming months, a UN climate envoy warned Friday. "The crisis has yet to peak," Macharia Kamau, special envoy on El Nino and climate, said at the end of a four-day trip to Mozambique. The devastation, which has affected some 18 million people across the southern African region, will be at its worst around January next year, he said. Mozambique, with 1.5 million people reeling from the drought, is one of the worst-hit countries, along with Zimbabwe, Malawi, Lesotho and southern Madagascar.