The World Health Organization (WHO) representative in Sudan said on Tuesday there was a "high risk of biological hazard" after one of the sides in the Sudan fighting seized a laboratory.
Britain launched a large-scale evacuation of its citizens from Sudan on Tuesday, joining other nations racing to get their people out of the North African country after its warring factions agreed to a 72-hour ceasefire.
The conflict between Sudan's army and a paramilitary group called the Rapid Support Forces (RSF) has triggered a rush to extract foreign diplomats and citizens.
Italy has rescued 47 boats carrying around 1,600 migrants in the central Mediterranean sea in the last two days and brought them ashore to the island of Lampedusa.
British foreign minister James Cleverly said he had spoken to the leaders of warring factions in Sudan to help facilitate the evacuation on Tuesday of British citizens from the North African country.