Ethiopia has blamed "unchanged stances" plus "additional and excessive demands of Egypt and Sudan" for the failure to find an agreement in the latest round of talks about the Grand Ethiopian Renaissance Dam (Gerd).

Nevertheless, in a statement the country's water ministry said that the current process, which is being led by the African Union, is at a "very encouraging state".

The three countries have been trying to resolve differences over Ethiopia's massive hydroelectric dam project for nearly a decade.

The construction of the Gerd, which straddles the Blue Nile upstream of Egypt and Sudan, is almost complete.

Egypt, which relies almost entirely on the Nile for its water needs, is worried that Ethiopia would be able to control the flow of the river.

Ethiopia appears to be on the brink of beginning to fill the dam and disputes continue about the speed of the filling as well as water flow once the dam is full.

It is not clear from the Ethiopian government statement exactly what new demands Egypt had come up with. But Ethiopia did say that the three countries had reached an "understanding on their interests instead of reiterating their positions".

Ethiopia says it expects negotiations to continue.

The Egyptian irrigation ministry's spokesman said that the final meeting on Monday between the three countries' water ministers "reflected the ongoing disputes" over the filling and operation of the dam, BBC Monitoring reports.