By Nita Bhalla BBC, Addis Ababa

Rising ethnic conflict in Ethiopia's north eastern region of Afar is aggravating the food crisis says the United Nations.

Thousands of pastoralists have fled the food crisis with their livestock.

The UN Emergency Unit for Ethiopia (UNEUE) said on Tuesday that the nomadic Afaris are being prevented from reaching grazing pastures because of long-standing conflicts with the ethnic Issa, Kereyu and Ittu groups.

Armed men have now taken over the job of protecting their herds

United Nations

Earlier this month, President of the Afar region, Ismail Ali Sero, warned that more than 250,000 Afaris had migrated out of their usual areas because of food shortages.

He appealed for intervention, claiming that a humanitarian crisis was in the making in the region.

The UN report says the crisis in the Afar region and its surroundings has been caused by various conflicts over resources among the four tribes.

Dry wells

Francois Piguet, author of the report, said that these conflicts have forced Afari pastoralists to change their usual migration patterns.

He said they were now being denied access to traditional water points, as well as grazing areas for their livestock.

To make matter worse, there has been no rains for more than two weeks in the whole of Afar region.

The poor rains have reportedly sucked wells and rivers dry, forcing women to trek for up to seven hours a day to find water.

Livestock, which are the main means of survival for Afari pastoralists, are also dying.

Afari herdsmen were said to be fleeing along with their surviving animals to the neighbouring states of Amhara, Oromia and Tigray.

They have been abandoning women, children and the elderly to their own fate.

"The drought has severely affected children and the elderly in particular, and unless urgent steps are taken, it will be a tragedy," President Ali Sero warned last month.

Malnutrition fears

The UN report emphasised that the fighting between the various ethnic groups, which began in March this year, has contributed to the limited movement of animals in certain areas, and have jeopardized the traditional division of work.

"Disturbance of the traditional pastoral labour division makes pastoral life more difficult because livestock has to be accompanied by armed guards," the report says.

The UN wants urgent action

"Women are no longer tending livestock and armed men have now taken over the job of protecting their herds."

Although there are no reports of malnutrition yet, the UN say that "people will face serious problems in the next few weeks if the situation is not addressed quickly and efficiently."

Particularly hard hit are Awash Fentale district in Afar Region and Fentale district in Oromia Region.

The Kereyu pastoralists are coping by cutting grass and sugar cane tops to feed livestock.

Bad forecast

The Afari pastoralists are already facing a severe shortage of cow milk.

They are now using sugar mixed with coffee shells and milk powder.

Camel milk is also insufficient.

If the dry season continues, pastoral groups will be forced to move near relatively favourable areas, a situation which could increase the potential for renewed clashes.

To add to the problem, the weather forecast for Afar for the next three months, does not look very promising.

On average, the region receives 300 mm of rainfall a year - a quantity which can fall in the capital, Addis Ababa, in a single month.

Afar, which has a population of 1.2 million, is a lowland region, constituting one-fifth of the territory of Ethiopia.