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Egypt and Ethiopia have once again locked horns in a fresh row over the latter's massive dam project, Grand Ethiopian Renaissance Dam (GERD), which is being built in the main tributary of the Nile River.
The new development comes after Cairo issued a fresh warning saying that 'all options are on the table' to deal with any threats to its water supply posed by the Ethiopian mega-dam.
"All options are open, and all alternatives remain available, and Egypt has its capabilities and its foreign relations," Egyptian Foreign Minister Sameh Shoukry warned on Wednesday.
"We just declare all options open without defining specific procedures, and this serves the Egyptian interest in retaining all available alternatives'" Shoukry said adding Egypt takes disciplined stances towards Ethiopian "intransigence"
A day later, Addis Ababa angrily responded dismissing as "irresponsible" the remarks by the Egyptian Foreign Minister.
"Such a threat constitutes a flagrant breach of the United Nations Charter and Constitutive Act of the African Union," Ethiopia's Ministry of Foreign Affairs said in a statement issued later on Thursday.
"This also stands as a clear violation of the Agreement on the Declaration of Principles on the Grand Ethiopian Renaissance Dam (GERD) signed on 23 March 2015 between Ethiopia, Egypt and Sudan."
"Egypt must stop its callous and unlawful pronouncements" the statement added.
Ethiopia called upon all concerned actors to take note of what it described as Egypt's flagrant violation of principles of international relations, underscoring that no interest can be advanced through threats and intimidation.
"If approached in good faith and with full respect for principles of international law, an amicable solution between the three countries is within reach in the negotiations under the auspices of the African Union" the Ethiopian statement stated.
"Yet again, Ethiopia reiterates its calls on the parties to re-engage the African Union platform and reach a negotiated solution on the GERD. On its part, Ethiopia remains committed to a win-win settlement of this matter", the statement noted.
Ethiopia, Sudan and Egypt have been locked in talks for about a decade over the dam, after Addis Ababa broke ground on the project in 2011.
In his Wednesday remarks, Shoukry accused Ethiopia of having lack to reach a binding agreement with Egypt and Sudan over the long-standing dispute on GERD.
"Egypt's signing of the Agreement of Principles with Ethiopia was an expression of its goodwill, but unfortunately we did not find flexibility on the Ethiopian side," Shoukry said.
The Egyptian Minister however said his country will "continue to interact with all countries to resolve the water dispute despite lack of commitment from the Ethiopian side.
Cairo and Khartoum fear that the mega-dam project would eventually diminish their historic water shares from the Nile River and hence consider the Ethiopian dam as a threat to their water security.
They insist Ethiopia halts water-filling operations until the parties reach a legally binding agreement with Ethiopia on the overall operation of the dam.
Addis Ababa, however, argues that the dam will not have a significant impact on the natural water flow into the downstream countries.
Last week, the Ethiopian government accused the Arab League States of "politicising" the Nile dam issue.
The accusation comes after the 22-member League passed a resolution regarding the filling and operation of the Grand Ethiopian Renaissance Dam (GERD).
The Arab League Thursday last week passed a resolution supporting Egypt's historic water rights from the Nile River resources.
In her reaction, Adis Ababa accused the League of being biased on its position over the long-standing dispute on GERD between Ethiopia and the downstream countries, Sudan and Egypt.
"The League is once again serving as the spokesperson of one state, disregarding basic principles of international law," the Ethiopian Ministry of Foreign Affairs said in a statement last Friday.
"Such attempts to politicize the issue of GERD neither advance friendly relations nor support the efforts to arrive at amicable solutions, as they are not based on facts or supported by law," the statement added.
"We should not have to remind the League that the Nile River and all the riparian countries are found in Africa," the Ethiopian statement further said.