The United Nations on Friday called for $40 million to fight a plague of desert locusts that has ravaged the Horn of Africa for years and is now spreading into Yemen and Saudi Arabia. UN spokesman Farhan Haq said recent heavy rains in the Horn of Africa have caused an upsurge in the number of locusts on both sides of the Red Sea, threatening food security for millions across the region. “Widespread seasonal rains have caused extensive breeding of locusts in eastern Ethiopia and Somalia and a new generation of desert locust swarms is now threatening to affect food security in these vulnerable areas,” Mr Haq told reporters. “Breeding is also underway on both sides of the Red Sea, posing a new threat to Eritrea, Saudi Arabia, the Sudan and Yemen.” The UN’s Food and Agriculture Organization (FAO) is seeking funding for “surveillance and control operations” in the worst-affected countries — Ethiopia, Kenya, Somalia, Sudan and Yemen, for 2021, added Mr Haq. More than 35 million people are already at risk of going hungry in those five countries and the numbers could grow by another 3.5 million if funding for fighting locusts runs out early next year, the FAO says. Thanks to past donations of $200m, about 1,500 people have been trained to monitor and control the biggest plague of locusts seen in seven decades using a fleet of 20 aircraft and 110 field-spraying vehicles, the FAO says. "We have achieved much, but the battle against this relentless pest is not yet over," said FAO director-general Qu Dongyu. "We must not waver. Locusts keep growing day and night." The desert locust is native to Africa, the Middle East and western Asia and is the world’s most destructive insect. It weighs only two grams but manages to eat its own weight in food every day. Favourable breeding conditions can lead to overcrowding and food shortages for locusts, which then gather into a swarm. Swarms of as many as 80 million locusts can cover several hundred square kilometres and travel 130km or more per day.