Egypt has said it is committed to the course of US-sponsored negotiations on Ethiopia's disputed Nile dam project after Addis Ababa said it would not take part in what was due to be the final round of talks to resolve the years-long crisis.

The Ethiopian water ministry said earlier on Wednesday that Addis Ababa will not take part in talks with Egypt and Sudan scheduled for Thursday and Friday in Washington, as it "has not completed its discussions with domestic stakeholders" on the dam. It said it had briefed the US treasury about the decision.

Hours later, the Egyptian foreign ministry said Cairo "is committed to the course of negotiations sponsored by the United States and the World Bank," affirming that Egypt's foreign and water ministers will take part in this week's talks that are intended to put the final touches on a deal on the filling and operation of the 6,000-megawatt hydropower dam.

"Egypt's participation in the meeting is in line with the Egyptian approach, which reflects goodwill and a sincere desire to reach a final agreement on the filling and operation of the dam," the statement added.

Also on Wednesday, the Ethiopian ambassador in Washington Fitsum Arega said his country "will not sign any agreement that will give up its right to use the Nile."

Egypt, Ethiopia and Sudan said in late in January that they would sign an agreement by the end of this month to iron out differences over the filling and operation of the $4.8 billion Grand Ethiopian Renaissance Dam.

The Sudanese Irrigation Minister Yasser Abbas said earlier this week that the three regional powers received a draft deal prepared by the US Treasury on the mechanism of filling and operating the dam.

The three countries agreed last month on a schedule for the staged filling of the dam and mitigation mechanisms to adjust its filling and operation during dry periods and drought. Details about other aspects were still due to be finalised.

Ethiopia hopes the mega project will help it become the continent's biggest power exporter, but Cairo fears that the dam will diminish its water supply from the Nile.