Ethiopia has rejected Egypt’s proposal over how to operate the Grand Renaissance Dam, which is being built on the Blue Nile near Ethiopia’s border with Sudan.
Egypt depends on the River Nile for water and is worried that the damn will worsen shortages.
Ethiopia’s Water Minister Seleshi Bekele said Egypt wanted the dam, which is nearly 70 per cent complete, to release 40 billion cubic metres of water every year.
“This is not right. We do have also our own future development needs. It also puts pressure on Sudan if that amount of water passes through," said the minister.
He had called the press conference in the capital, Addis Ababa, after arriving back from a River Nile meeting in Egypt's capital, Cairo.
Hydroelectric power stations do not consume water, but the speed with which Ethiopia fills up the dam’s reservoir will affect the flow downstream.
“We have a plan to start filling on the next rainy season, and we will start generating power with two turbines on December 2020,” Mr Seleshi said.
Egypt’s other proposal, about the Aswan Dam, was also unacceptable, the Ethiopian minister said.
According to Mr Seleshi, Egypt wants the level of water at Aswan to remain at a height of 165m (541ft) - and should the level drop for the Renaissance dam to release water.
“This we don’t accept,” he said.
Over the weekend, Egyptian President Abdul Fattah al-Sisi was quoted in local media as saying that the Blue Nile dam project would never have got under way in 2011 had Egypt not been distracted by the Arab Spring uprising.