KHARTOUM (Reuters) - Ethiopia's prime minister and Sudan's leadership said on Tuesday they would make every effort to reach a deal on a giant hydropower dam on the Blue Nile that has caused a bitter dispute between Addis Ababa and Cairo over water supplies.


Ethiopia, Egypt and Sudan failed to strike an agreement on the operation of the Grand Ethiopian Renaissance Dam (GERD) before the reservoir behind the dam began being filled in July. But the three countries have returned to talks under African Union mediation.


Ethiopian Prime Minister Abiy Ahmed visited Khartoum on Tuesday with a high level delegation to meet Sudanese officials, who have played an increasingly prominent role in negotiations with their two neighbours.


"The two sides emphasised they would make every possible effort to reach a successful conclusion to the current tripartite negotiations," a joint statement from Ethiopia and Sudan said.


The talks should lead to a formula that makes the dam a tool for regional integration, the statement said, praising AU mediation as embodying "African solutions for African problems".


Negotiations have previously faltered over a demand from Egypt and Sudan that any deal should be legally binding, over the mechanism for resolving future disputes, and over how to manage the dam during periods of reduced rainfall or drought.


Egypt says it is dependent on the Nile for more than 90% of its scarce fresh water supplies, and fears the dam could have a devastating effect on its economy.