Egypt said a fourth round of talks over a giant dam being built on the Nile River by Ethiopia has failed, and reiterated its right to defend its water and national security interests.

The comments, issued late Tuesday by Egypt’s Irrigation Ministry, capped discussions with Sudan and Ethiopia aimed at securing an agreement on the rule for filling and operating the Grand Ethiopian Renaissance Dam. The talks follow a meeting between Egypt’s president and Ethiopia’s prime minister earlier this year.

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Egypt attributed the failure to “Ethiopia’s persistent refusal, that marked its posture over the course of recent years, to accept any of the technical or legal compromise solutions that would safeguard the interests of all three countries,” the ministry said in a statement after talks in the Ethiopian capital, Addis Ababa.

“It has become evident that Ethiopia elects to continue exploiting the negotiation process as a cover to solidify a fait accompli on the ground,” it said, adding that Addis Ababa is using the talks as an “instrument of approval from the downstream countries of an unregulated and absolute Ethiopian control of the Blue Nile.”

Read More: Deadlock on Nile as Ethiopia-Egypt Dam Talks Yield Little

Earlier discussions yielded no tangible results for Egypt or Sudan, both of whom are concerned that the giant dam on one of the main tributaries of the Nile will curb access to the river that provides most of their fresh water.

Egyptian President Abdel-Fattah El-Sisi, who this week was re-elected to a third term, has said the country’s water rights are a “red line” and warned against any efforts to curtail them.

Egypt will “closely monitor the filling and operation of the GERD and reserves its right, in accordance with international charters and accords, to defend its water and national security in the event of harm,” the Irrigation Ministry said in a statement.

Ethiopia took issue with Egypt’s comments, dubbing them a misrepresentation of the situation and adding that Egypt “maintained a colonial- era mentality and erected roadblocks against efforts toward convergence,” according to a Foreign Ministry statement.