Egypt has made good on its promise to explore alternative avenues to settle its deepening water dispute with Ethiopia, writing to the UN Security Council this weekend asking for its intervention to persuade Addis Ababa to return to the negotiating table. Egypt’s Friday letter was sent two days after the latest round of negotiations on the operation of a massive hydroelectric dam being built by Ethiopia on the Nile ended without a breakthrough, a failure Cairo has blamed on Ethiopian “intransigence.” Adding to the urgency, the letter was sent at a time when Ethiopia remained defiantly adamant it would start filling the reservoir behind the dam next month regardless of whether an agreement with Egypt and fellow downstream nation Sudan was reached. "For us it is not mandatory to reach an agreement before starting to fill the dam, hence we will commence the filling process in the coming rain season," Ethiopian Foreign Minister Gedu Andargachew said in an interview with the<em> Associated Press</em> on Friday night. “If we have to wait for others’ blessing, then the dam may remain idle for year, which we won’t allow to happen.” Egypt fears the hydroelectric dam on the Blue Nile, which originates on the Ethiopian highlands and accounts for more than 80 per cent of the river’s water, will significantly reduce its vital share of the river’s water. It has been trying to persuade Ethiopia to reach a deal that would minimise the impact on its water share and make provisions for future spells of drought. Ethiopia, for its part, says the dam is key to its development plans and accuses Egypt of clinging to colonial-era treaties that unfairly gave it the lion’s share of the river water without heed to the needs of the 10 other Nile basin countries. It considers Cairo’s demands as an infringement on its sovereignty. Egypt and Ethiopia have in recent months engaged in a bitter war of words over the dam, with some sabre rattling occasionally featuring in their rhetoric. Egyptian President Abdel Fattah El Sisi has described the dam dispute as an existential issue but has never spoken publicly about military action. Although unlikely, any military action by Egypt against Ethiopia would face challenges. The two countries, for example, do not share a border and any intervention would prove difficult to justify as a legitimate act of self-defence. On Saturday, Mr El Sisi, a former general, spoke briefly to members of air force and commando units stationed in Egypt’s western region. He said his country’s armed forces ranked among the best in the region but cautioned that their doctrine was not aggressive or threatening. Addressing the men gathered around him, however, he added: “Be prepared to carry out any mission here inside our borders or, if need be, outside of our borders.” Egypt has in recent years acquired cutting-edge hardware that allows it to operate militarily far beyond its borders. These include German-made submarines, French jet-fighters and troop carrier ships equipped with Russian-made assault helicopters. Significantly, Egypt’s letter to the UN Security Council did not ask for punitive measures against Ethiopia if it acted unilaterally. Instead, it wanted the council “to affirm the importance of the three countries resuming the negotiations with goodwill … to reach a fair and balanced solution.” The letter also blamed Ethiopia’s “not positive positions” for the lack of progress in the talks, which began nearly a decade ago. “In view of the fact that the Nile water amounts to an existential issue for Egyptians, Egypt has asked the Security Council to shoulder its responsibility and intervene to avoid any form of tension and to safeguard international peace and security,” the Egyptian Foreign Ministry said in a statement. Egypt on Wednesday said Ethiopia was resisting signing a deal that was binding under international law and instead only wanted guidelines on the operation of the dam. It also refused the creation of a binding legal process to settle future disputes or commit to effective measures for any future drought. To Sudan, the dam, being built close to its border, does not have the vast potential for damage Egypt fears. But there are concerns a structural breach in the dam would flood large swathes of its territory. Lack of co-ordination on the running of the dam, moreover, could impact Sudan’s power generation from its own Blue Nile dams. The dam also holds promise for the people of Sudan, with the prospect of cheap power and the prevention of the annual flooding the Blue Nile causes. “The ability to regulate the Blue Nile means no more flooding … There is also the potential for increased irrigation,” William Davison of the International Crisis Group told an online media briefing on Wednesday. “The regulated flow of the Blue Nile can allow Sudan to produce more power from its dams.”