YEMEN - Yemen faces the world's largest famine in decades "with millions of victims" if aid deliveries are not resumed, a senior UN official has warned. Mark Lowcock, the UN under-secretary general for humanitarian affairs, urged the Saudi-led coalition to lift its blockade of the conflict-torn country. On Monday, the coalition shut air, land and sea routes into Yemen after Houthi rebels fired a missile at Riyadh. The ballistic warhead was intercepted near the Saudi capital. The Red Cross said its shipment of chlorine tablets, vital to combating a cholera epidemic which has affected more than 900,000 people, had been blocked. More than 8,670 people - 60% of them civilians - have been killed and 49,960 injured in air strikes and fighting on the ground since the coalition intervened in Yemen's civil war in March 2015, according to the UN.