Ethiopian Prime Minister Abiy Ahmed has insisted the facility on the Blue Nile poses no harm, seeking to calm the fears of downstream Egypt and Sudan

Ethiopia has officially inaugurated Africa's largest hydroelectric plant, a controversial project expected to generate up to 5.15 gigawatts of power for the landlocked nation, where nearly half the population is estimated to lack access to electricity.

The inauguration of the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile on Tuesday went ahead despite fierce opposition from downstream Egypt and Sudan, which fear the project will disrupt vital water flows.

"To our brothers: Ethiopia built the dam to prosper, to electrify the entire region and to change the history of black people," Ethiopian Prime Minister Abiy said as he addressed a crowd that included the presidents of Djibouti, Kenya, Somalia, and South Sudan. The prime ministers of Eswatini and Barbados, the chairperson of the African Union Commission, and the United Nations under-secretary-general and executive secretary of the Economic Commission for Africa were also in attendance.

"It is absolutely not to harm its brothers," Abiy stated.

In a post on X, Ethiopian President Taye Atske Selassie hailed the GERD as "a reward of Ethiopian people's resilience," declaring, "Let there be eternal light!"

Addis Ababa announced the completion of the facility, among the 20 biggest in the world, in July after a 14-year construction period. It was initially scheduled to be completed within six years on a $4 billion budget, although Ethiopian authorities now put the final cost at about $5 billion. US President Donald Trump had claimed that Ethiopia built the dam "largely" with American money, but the GERD Coordination Office dismissed the allegation as false and "destructive," stressing that the project was entirely financed by the government and local contributions.

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Local media reported jubilation across Africa's second most populous country following the "historic" opening of the plant, which authorities have long hailed as a milestone for Ethiopia's renaissance.

According to the World Bank, only about 55.4% of Ethiopia's population had access to electricity as of 2023, compared with universal coverage in Egypt at 100%. Egypt, which relies on the Nile for about 97% of its fresh water, has accused Addis Ababa of violating international laws and has taken the dispute to the UN Security Council.