Ethiopia announced on Sunday it has filled its Grand Renaissance Dam on the Nile, the source of a long-running water dispute with downstream Egypt and Sudan.
The news brought a prompt condemnation from Egypt, who denounced it as illegal.
Ethiopia's announcement came just a fortnight after the three countries resumed negotiations, after a lengthy break, on an agreement which takes account of the water needs of all three.
Egypt and Sudan fear the massive $4.2-billion dam will severely reduce the share of Nile water they receive and have repeatedly asked Addis Ababa to stop filling it until they have all reached agreement on how it should work.
"There was a lot of challenge. We were many times dragged to go backwards. We had an internal challenge and external pressure. We've reached (this stage) by coping together with God," Abiy said.
"I believe that we will finish what we have planned next," he said.
The Ethiopian government’s communications service said on X that the dam, arguably the largest in Africa, was "a gift to generations".
Sudan did not immediately react to the announcement.
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