Evacuees, believed to be British nationals, arrive at Stansted Airport following evacuation from Sudan, on Wednesday. Reuters

A 72-hour ceasefire between Sudan's warring factions was set to expire late on Thursday though efforts were under way to extend it.

Britain started the airlift late on Tuesday. Cypriot Foreign Minister Constantinos Kombos said 391 people had flown to Larnaca airport in Cyprus from Sudan by mid-afternoon on Wednesday.

In London, a spokesperson for Prime Minister Rishi Sunak said eight repatriation flights would leave Sudan by the end of Wednesday. Evacuees were being flown on to Britain from Cyprus.

"This is just the beginning of an operation," British High Commissioner to Cyprus Irfan Siddiq told reporters, adding the UK government had 2,500 Britons registered in Sudan.

Britain previously estimated that around 4,000 Britons were stuck in Sudan.

Siddiq, a former British ambassador to Khartoum, said authorities were encouraging people in Sudan to make their way to the Khartoum airport to board evacuation flights while the ceasefire appeared to be holding.

"The situation on the ground in Khartoum is extremely volatile. We simply don't have the means to escort people to the airport," he said.

Reuters