The United Nations (UN) appealed on Wednesday for $4.1-billion to meet the humanitarian needs of civilians caught up in the war in Sudan, as well as those who have fled to neighbouring countries.

A ten-month war in Sudan between its armed forces and the paramilitary Rapid Support Forces (RSF) has devastated the country's infrastructure, prompted warnings of famine and displaced millions of people inside and outside the country.

Half of Sudan's population - around 25-million people - need humanitarian assistance and protection, while more than 1.5-million people have fled to the Central African Republic, Chad, Egypt, Ethiopia and South Sudan, according to the UN.

In its joint appeal with the UN refugee agency (UNHCR) launched on Wednesday, the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) called for $2.7-billion in funding to provide humanitarian aid for 14.7-million people.

The UN refugee agency asked for $1.4-billion to support nearly 2.7-million people in five countries neighbouring Sudan as part of the appeal.

"Ten months of conflict have robbed the people of Sudan of nearly everything: their safety, their homes and their livelihoods," UN aid chief Martin Griffiths said. "But last year's appeal was less than half funded. This year, we must do better and with a heightened sense of urgency."