Ethiopia made progress with Egypt and Sudan in US-brokered talks over a controversial dam on the Nile, with an agreement to fill it only during the rainy season.
The three countries had set a deadline of Wednesday to reach an accord over the Grand Renaissance Dam in Ethiopia, which Egypt fears could deplete its scarce drinking water.
After three days of talks in Washington, they stopped short of announcing a resolution, saying the three countries would meet again in the US capital on January 28-29 to finalize an agreement.
Analysts have feared that the three Nile basin countries could be drawn into a conflict if the dispute is not resolved before the dam begins operating.
In a draft deal, Ethiopia agreed that it will fill the dam -- set to be Africa's largest hydroelectric project -- only in the wet season from July to August, or also in September if conditions are right.
Ethiopia will aim rapidly to reach the level of 595 meters (1,952 feet) above sea level, with later filling to be determined based on the conditions of the river.
The filling "will be executed in stages and will be undertaken in an adaptive and cooperative manner that takes into consideration the hydrological conditions of the Blue Nile and the potential impact of the filling on downstream reservoirs," said a joint statement released by the United States.
The three countries' foreign ministers "reaffirmed the importance of transboundary cooperation in the development of the Blue Nile to improve the lives of the people of Egypt, Ethiopia, and Sudan, and their shared commitment to concluding an agreement," it said.
Ethiopia says the $4.2 billion hydroelectric barrage would double its electricity and be indispensable for a growing economy. It is expected to begin generating power by the end of 2020 and be fully operational by 2022.
But Egypt fears disruption in the river that provides 90 percent of its drinking water.
Discussions between the three countries broke down, prompting Egypt to call for international mediation.
The US Treasury Department agreed to broker talks after Egyptian President Abdel Fattah al-Sisi made a pitch to President Donald Trump, his close ally.