The prime ministers of Egypt and Sudan discussed Ethiopia’s controversial dam project on the River Nile during a meeting held on Tuesday via video conference that was attended by both countries' intelligence chiefs and irrigation and foreign ministers. 

Egypt's Prime Minister Mostafa Madbouly and his Sudanese counterpart Abdalla Hamdok discussed “all aspects” of the Grand Ethiopian Renaissance Dam (GERD) during the meeting, Egypt’s foreign ministry said in a statement late on Tuesday.

The massive $4.8 billion mega project, under construction on the Blue Nile since 2011, has triggered a diplomatic row between Egypt and Ethiopia.

During the meeting, Hamdok said he will call Ethiopian Prime Minister Abiy Ahmed to “discuss the resumption of the tripartite negotiation as soon as possible,” Sudan’s official news agency SUNA said.

Cairo and Khartoum stressed during the meeting “the need to reach a tripartite agreement that takes into account the interests of the three countries, and to continue negotiations based on what was agreed upon in Washington,” SUNA added.

The US, represented by the Treasury Department, along with the World Bank stepped in last year to host tripartite negotiations that began in November after years-long negotiations between the three countries hit a dead end.

Following four months of negotiations brokered by Washington, during which the three nations initially agreed on mitigation mechanisms to adjust the filling and operation of the dam during dry periods and drought, the US and the World Bank drafted a deal that was due to be signed in late February. 

Ethiopia skipped the latest round of talks and only Egypt initialled the deal.

Ethiopian Irrigation and Electricity Minister Sileshi Bekele said on Tuesday that his country has the right to use the 86 percent share of water it contributes to the River Nile, stressing the dam has no significant harm on any of the downstream countries, according to the Ethiopian News Agency ENA. 

Also on Tuesday, the United Nations Secretary-General Antonio Guterres called on Egypt, Ethiopia and Sudan to “peacefully resolve any remaining differences and to achieve a mutually beneficial agreement.”

Ethiopia has backpedalled on a 2015 Declaration of Principles deal that obliges the three African countries to reach an agreement on the guidelines of filling and operating the dam, telling the UN Security Council (UNSC) in a 14 May letter that it “does not have a legal obligation to seek the approval of Egypt to fill the dam.”

Article 5 of the Declaration of Principles stipulates that all three countries should reach an agreement on the rules of filling and operating the 6,000-megawatt dam before starting the process of filling the reservoir.

Ethiopia’s 22-page letter to the UNSC came in response to an Egyptian letter sent to the president of the UNSC on 1 May stressing Egypt’s "unwavering commitment" to concluding a comprehensive agreement on the GERD based on the 2015 deal.

According to the Egyptian letter, the Ethiopian prime minister sent on 10 April a letter to the president of Egypt and the prime minister of Sudan proposing they agree to an Ethiopian plan covering only the first stage of the filling of GERD.

The Ethiopian proposal was rejected by both countries, the Egyptian 17-page letter said, stressing that any agreement on the GERD must be comprehensive and "must regulate the complete process of filling the dam and its operation".

Egypt also blamed Ethiopia for trying to establish a deal without taking the interests of downstream countries into consideration, the letter noted.

Last week, Sudan joined Egypt in repudiating efforts by Ethiopia to progress its mega-dam, with Hamdok sending a letter to his Ethiopian counterpart disapproving of Addis Ababa’s proposed agreement which he said lacks several technical and legal aspects, according to the Sudanese cabinet.

"The signing of any partial agreement for the first stage cannot be approved as technical and legal aspects must be incorporated in the agreement, including the coordination and data exchange mechanism, dam safety and environmental and social impacts," Hamdok said in his letter.

Ethiopia hopes the massive $4.8 billion megaproject on the Blue Nile will allow it to become Africa’s largest power exporter.

But Egypt, which relies on the Nile for the vast majority of its freshwater, fears the dam will diminish its water supply that has already been below scarcity level.

Egypt has a water share of around 570 cubic metres per person annually, well below the water scarcity level of 1,000 cubic metres per person per year. The figure is expected to drop further to 500 cubic metres by 2025.