Egypt on Wednesday called for a legally binding deal with Ethiopia over the Grand Ethiopian Renaissance Dam (Gerd), saying the Nile’s water is an “existential issue”. Cairo fears the dam, which is nearly 80 per cent complete, would deeply reduce its vital share of the river's water. Egyptian President Abdul Fattah El Sisi made the comments during talks in Cairo with Burundi's president, Evariste Ndayishimiye. Egypt and Burundi are among 11 countries covered by the Nile's drainage basin. “It’s an existential issue that impacts the lives of millions of Egyptians,” Mr El Sisi said. “It is necessary that a legally binding agreement regulating the filling and operation of the dam be reached as soon as possible away from unilateral actions that seek to create a fait accompli and ignore people’s basics rights.” The Egyptian leader was referring to Ethiopia's intention to go ahead with a second and much larger filling of the Gerd in July, regardless of whether a deal has been reached with Egypt and fellow downstream nation Sudan. Mr El Sisi has only once before described the Gerd's likely impact on Egypt's share of the Nile water as an existential issue. The second filling will involve 13.5 billion cubic metres – nearly three times the size of the first filling last year. That disrupted work in several of Sudan’s water treatment facilities but had no impact on Egypt, as flooding had filled its Aswan dam reservoir close to capacity. Egypt and Sudan have for years been trying to persuade Ethiopia to enter a deal that governs the operation of the dam and puts in place mechanisms to resolve disputes and the handling of persistent drought. Ethiopia says non-binding guidelines should be sufficient. With a population of 100 million people almost entirely dependent on the Nile for fresh water, Egypt has been alarmed by the prospect of a deep cut in its share of the river’s water. It fears a reduced share would wipe out tens of thousands of jobs and disrupt its delicate food supply system. Sudan maintains that it could suffer deadly flooding and a disruption of its own power-generating Nile dams if Ethiopia did not share real-time data on the operation and filling of the dam, which stands less than 20 kilometres from its border with Ethiopia. In response to Ethiopia’s perceived intransigence, Sudan and Egypt have been forging closer ties in recent months, exchanging top-level visits, building a rail link between the two nations and incorporating Sudan in Egypt’s electricity grid. The two have also signed a military co-operation pact. Separately, Sudan and Ethiopia are locked in a border dispute that has led to a string of deadly clashes between the two sides that have raised the prospect of a border war. The clashes followed a move by the Sudanese military late last year to wrest back control of a border enclave long settled by Ethiopian farmers and protected by federal troops and allied militias. Ethiopia says it will not negotiate a resolution of the dispute until Sudan pulls out from the areas it has retaken. It has also accused the Sudanese military of escalating the dispute for the benefit of its Egyptian allies. But Ethiopian Prime Minister Abiy Ahmed appeared to have softened his position on the dispute in comments made on Tuesday in Ethiopia's Parliament. “Sudan has its own problems. So does Ethiopia. Faced with these difficulties, both need not go to war. It’s therefore better to solve the border conflict through dialogue,” Mr Abiy said. The people of Sudan, he added, are “brothers who have been standing alongside us in every situation”.