UNITED NATIONS, March 17 (Xinhua) -- The United Nations is ready to facilitate an agreement between Ethiopia, Egypt and Sudan on a Nile dam, said a spokesman on Wednesday.

Stephane Dujarric, spokesman for UN Secretary-General Antonio Guterres, said the world body has received a letter from Sudanese Prime Minister Abdalla Hamdok on the issue.

"We reiterate our readiness to support all efforts toward reaching an agreement on the Grand Ethiopian Renaissance Dam," he told a daily press briefing. "Mr. Guterres welcomes initiatives to move the negotiations forward and awaits agreement from all the parties as to how the UN can best support the process."

Before any UN engagement, all the parties involved in the dispute need to agree on mediation, he said.

Ethiopia, an upstream Nile basin country, started building the dam in 2011, while Egypt is concerned that the dam might affect its annual share of the Nile waters. Sudan has recently been raising similar concerns. Over the past few years, tripartite talks on the rules of filling and operating the dam with a total capacity of 74 billion cubic meters, have been fruitless. Enditem