By Emma Farge

GENEVA Aid workers say fighting between rival military factions in Sudan is pushing poorly-funded humanitarian programmes in the region to a breaking point.

Even before the violence began on April 15, millions of people in Sudan and neighbouring countries were dependent on aid due to poverty and conflict. Since then, hundreds have been killed, including at least five humanitarians; food stocks have been looted; and many international aid workers have left.

The U.N. refugee agency UNHCR is seeking an additional $445 million to cope with an expected exodus of 860,000 people to six of Sudan's seven neighbours - Chad, Egypt, Ethiopia, Eritrea, South Sudan and Central African Republic - by October.

Here are the needs broken down by country.

SUDAN

* More than 700,000 people have been displaced in Sudan since April 15, according to the International Organization for Migration. Before the fighting, 3.7 million people were already internally displaced, mostly in the Darfur region where violence has simmered since a major conflict in the early 2000s.

* The country hosts over 1 million refugees, most from South Sudan, Eritrea and Ethiopia's Tigray region.

* Before April 15, nearly 16 million people relied on humanitarian aid. An internal U.N. estimate obtained by Reuters shows this figure is expected to increase by 5 million, including 2.5 million children.

* A $1.75 billion U.N. aid programme for Sudan in 2023 is 15% funded.

SOUTH SUDAN

* Some 240,000 people are expected to flee from Sudan to South Sudan, UNHCR says. Already, some 35,000 have arrived, most of them by boat across the Nile to a border town called Renk.

* The country's $1.7 billion U.N. aid programme for the year is 26% funded.

CHAD

* Some 105,000 people fleeing Sudan are expected to cross the long desert border into Chad. Already, an estimated 30,000 have arrived.

* Chad has among the highest levels of hunger in the world, and more than a third of its children under 5 are stunted, the U.N. World Food Programme (WFP) says. It was already hosting more than 500,000 refugees, who have seen assistance reduced or cut since last year due to funding shortfalls.

* UNHCR says it needs additional funds to move new arrivals, who are currently sleeping in flimsy improvised shelters, into existing refugee camps and build five new ones.

* The U.N.'s $674 million programme for the year is so far only 4.6% funded.

EGYPT

* Egypt is expected to receive the bulk of Sudan's displaced, with 350,000 set to arrive, UNHCR says. So far, some 50,000 have entered the country, including many with disabilities.

ETHIOPIA

* Some 85,000 people are expected to flee to Ethiopia. About 1,500 have arrived already, including many Eritrean refugees who had sought shelter in Sudan. A U.N. report says early arrivals showed signs of psychological distress.

* Ethiopia already had a $4 billion U.N. aid programme for 2023, as it seeks to recover from a two-year war that killed tens of thousand of people and created famine-like conditions for hundreds of thousands. It is 20% funded.

CENTRAL AFRICAN REPUBLIC

* The country is expected to receive 25,000 people from Sudan. More than 6,000 have arrived already, UNHCR says.

* More than three-quarters of people in the country live in poverty, and nearly half are food insecure, WFP says.

* CAR needs nearly half a billion dollars in aid in 2023, the U.N. says. The programme is 23% funded.

ERITREA

* The country could receive some 55,000 people from Sudan, although none have been registered yet.

* Eritrea is one of Africa's poorest and most repressive states. Thousands flee the country each year to attempt the dangerous journey to Europe.

(Reporting by Emma Farge; Editing by Alexandra Zavis and Daniel Flynn)