The US envoy for the Horn of Africa arrived in Sudan Friday for talks on Ethiopia's controversial Nile dam and rising tensions over a fertile border region, Sudanese state media reported.
Egypt, Sudan and Ethiopia have been locked in inconclusive talks over the filling and operation of the huge hydro-power dam since Addis Ababa broke ground on it in 2011.
Cairo views the dam as an existential threat to its water supply, while Khartoum fears its own dams would be harmed if Ethiopia fills the reservoir without a deal.
Addis Ababa insists the barrage is indispensable for its development.
Sudanese Foreign Minister Mariam al-Sadiq al-Mahdi met US envoy Jeffrey Feltman at the airport in Khartoum, according to an AFP correspondent.
Feltman is expected to meet with head of state Abdel Fattah al-Burhan, Prime Minister Abdalla Hamdok and other senior Sudanese officials on his two-day visit, official news agency SUNA said.
"The talks will tackle the Grand Ethiopian Renaissance Dam and the border tensions between Sudan and Ethiopia," it added.
Feltman's visit comes as part of a regional tour that also takes in Egypt, Eritrea and Ethiopia, according to the US State Department.
Ethiopia, which announced last July it had completed its first-year filling target for the dam, has said it would proceed with the second stage regardless of whether an agreement is in place.
US and European Union observers have attended multiple rounds of negotiations between the three countries that have so far failed to produce a binding deal.
Tensions over the dam come amid souring relations between Sudan and Ethiopia over Al-Fashaqa, a fertile border region where Ethiopian farmers have long cultivated fertile land claimed by Sudan.
Khartoum and Addis Ababa have been locked in a tense war of words over the region, trading accusations of violence and territorial violations in the area.
