CAIRO/KHARTOUM (Reuters) - Egypt and Sudan criticised Ethiopia for what they called unilateral filling of its Blue Nile dam at a new round of talks that kicked off on Monday to regulate the flow of water from the huge project.


Sudan and Egypt both fear the $4 billion hydroelectric dam could lead to water shortages in their own countries. The Blue Nile is a tributary of the Nile, from which Egypt's 100 million people get 90% of their fresh water.


Almost a decade of tortuous negotiations have failed to yield an agreement to regulate how Ethiopia will fill the reservoir and operate the dam while protecting Egypt's scarce water supplies.


The Grand Ethiopian Renaissance Dam is being built about 15 km (9 miles) from the border with Sudan on the Blue Nile, which provides the bulk of the water in the Nile after it meets the White Nile in Sudan.


Last week, Ethiopia, which says it needs the dam to generate electricity for its people, said it had already achieved its first-year target for filling the reservoir, thanks to a heavy rainy season.


Egypt and Sudan expressed concerns about the "unilateral filling", which they said "cast a shadow on the meeting and raised many questions about the feasibility of the current course of negotiations and reaching a fair agreement", Egypt's Irrigation Ministry said in a statement.


Sudan said Ethiopia's action was "a harmful and disturbing precedent in the course of cooperation between the countries concerned", according to a statement from its Irrigation Ministry.


There was no immediate word from Ethiopia. Among the issues at stake in the talks, being hosted by the African Union, are how the dam will operate during "dry years" of reduced rainfall, and whether the agreement and its mechanism for resolving disputes should be legally binding.