WASHINGTON – Egypt is hinting once again at the possibility of conflict with Ethiopia amid the failure of the latest round of talks over the controversial Grand Ethiopian Renaissance Dam (GERD) last week.

The fruitless negotiations came as Cairo sent air forces to North Sudan for joint combat exercises with Khartoum’s military. Although the chief of staff of Sudan’s armed forces, Gen. Mohamed Osman al-Hussein, said the exercise was “not targeting a certain country,” Egyptian officials’ statements have been more ominous.

“I tell our Ethiopian brothers: 'We should not reach the level that you mess with a water drop in Egypt, because all options are open,'” Egyptian President Abdel Fattah al-Sisi said April 7 after the tripartite negotiations in Kinshasa collapsed. “Cooperation between each other and building together is much better than when we disagree and struggle.”

The latest setback makes Ethiopia’s vow to fill the dam’s reservoir for a second time before July all the more likely to be fulfilled despite the renewed warnings from Egyptian officials, who blamed Addis Ababa last week for rejecting a Sudanese proposal to bring in foreign mediation.