Background The rivalry over the Nile water is a major issue that threatens the stability of north-east Africa. The Nile has particular importance for Egypt and Ethiopia. It is a source of food and water for both countries and has a significant impact on their energy security as well. The dilemma over the flow of water rose after the Ethiopian Government announced that it had established the Great Ethiopian Renaissance Dam (GERD), which could affect the volume of water that Egypt receives. The Nile is Egypt’s lifeblood. A military confrontation is likely to occur in the future if diplomacy fails to achieve an adequate level of co-operation between Egypt and Ethiopia. Comment Egypt and Ethiopia have long struggled for control of the Nile. As far back as the 12th Century, the Ethiopian Emperor, Amda Syon, threatened to divert its waters unless the Egyptian Sultan stopped persecuting Coptic Christians. Securing the uninterrupted flow of the Nile from the Ethiopian highlands has therefore been a concern for Egyptian leaders since then, making it, arguably, both the oldest and most important foreign policy concern of this country. While Egypt is facing numerous issues, most notably a weak economy and increased division in public opinion, the announcement of the GERD has given it another major national security challenge. The Egyptian Government claims that the GERD will cause significant harm to its water supply. It predicts that the main dangers will be the reduction of energy generation and the decrease in the water level in Lake Nasser. Ethiopia announced the construction of the GERD during a period of political instability in Egypt, after the January 2011 revolution. That could explain why the Egyptian responses were not as circumspect as they were in the following years, when the political situation was more stable. For instance, President Mohammed Morsi, during an era of political floundering, opted to stir up public opinion against the GERD, by claiming that it threatened Egypt’s God-given rights. He referred to a water Jihad to protect the Egyptian water from the Christians, in a reference to Ethiopia. In addition, as further evidence of the political confusion during the Muslim Brotherhood era, Morsi was overheard on national television, along with other highly-positioned officials, detailing plans to strike the GERD and possibly intervene in Ethiopia’s internal politics. The current Egyptian president, Abdel Fattah al-Sisi, has stated that Ethiopia has the right to development provided that it does not harm Egypt. When it is built, the GERD will be the largest dam in Africa and a critical project that aims to develop the struggling state. The planned reservoir will have a volume of more than 63 million cubic metres, which is approximately 1.3 times the annual flow of the Blue Nile. In addition, the GERD will generate an estimated 6,000 Megawatts of hydroelectric power, which will triple Ethiopia’s current power output. Ethiopia emphasises its right to develop and cites the GERD as being the primary driver for its economic and social development and a critical tool for its food security. The two countries have a choice; they could allow their millennia-long rivalry over the Nile to become confrontational, or they could negotiate a mutually-beneficial co-operative approach to the situation. Analysts claim that the prospect of armed confrontation between Egypt and Ethiopia is very unlikely, despite military threats made during the Morsi presidency. The Egyptian army officers are closely connected to the United States, which would undoubtedly do everything to prevent them from taking aggressive military action that could destabilise the whole region. The Egyptians need, first of all, to be sure that the GERD will not harm them and that they can engage in constructive relations with Ethiopia. Recently, in a live press conference in Egypt, Sisi asked Abiy Ahmed, the Ethiopian Prime Minister to swear to God that the Ethiopian project would not hurt Egypt; Ahmed did that. Also, Egypt needs strong guarantees that the GERD will not harm its water supply. The most reliable guarantee would be economic co-operation between the two countries, to develop and achieve their mutual food, water and energy security. If the political leaders can reach that level of co-operation as quickly as possible, the military threat could be averted and both countries would be free to focus on their economic development.