Nigeria has secured a major legal victory in its long-running arbitration dispute with Sunrise Power and Transmission Company Limited over the controversial Mambilla Hydropower Project in Taraba State.
The International Chamber of Commerce (ICC) arbitration tribunal in Paris ruled in favour of the Federal Government on Thursday, September 17, 2026, following years of proceedings arising from a disputed agreement dating back to 2003.
Sunrise Power had sought about $2.35 billion in damages, alleging that Nigeria breached an agreement under which the company was to develop the 3,050-megawatt Mambilla hydropower project under a build-operate-transfer arrangement.
The company argued that Nigeria subsequently proceeded with another arrangement involving a Chinese consortium, contrary to its agreement.
The tribunal’s decision marks a significant development in a dispute that has spanned several administrations and involved former presidents, ministers and senior government officials.
Details of the tribunal’s full reasoning and the specific orders contained in the award were not immediately available at the time of filing this report.
Dispute and $200m Settlement
Sunrise Power commenced arbitration proceedings against Nigeria before the ICC in October 2017, seeking approximately $2.354 billion over the alleged breach.
The dispute took another turn in January 2020 when the Federal Government entered into a settlement agreement with the company.
Under the reported terms, Nigeria was to pay Sunrise Power $200 million within 14 days, with a 10 per cent penalty applicable in the event of default. In return, Sunrise Power was expected to resume its role as the local content partner for the Mambilla project.
The settlement was not implemented as envisaged, prompting further legal action.
In 2021, Sunrise Power filed another claim before the ICC, seeking $400 million over the Federal Government’s alleged failure to honour the settlement agreement.
How the Mambilla Dispute Started
The controversy dates back to 2003, when Sunrise Power was awarded a contract connected to the proposed Mambilla hydropower project.
The planned facility, located in Taraba State, was designed to generate about 3,050 megawatts of electricity and was expected to become one of Nigeria’s major hydroelectric projects.
Questions later emerged over the validity of the original contract award.
Former President Olusegun Obasanjo subsequently maintained that he had not authorised the award, arguing that a minister could not commit the Federal Government to a multi-billion-dollar project without presidential approval.
The contract also became linked to criminal proceedings involving former Minister of Power and Steel, Olu Agunloye.
In June 2025, an Economic and Financial Crimes Commission investigator told a Federal Capital Territory High Court that Obasanjo had confirmed that he did not approve the contract.
The EFCC has accused Agunloye of awarding the contract without the required approvals and alleged that he received payments connected to Sunrise Power. Agunloye has pleaded not guilty and denied the allegations.
Former Presidents Testify
The arbitration proceedings attracted significant attention after former presidents Obasanjo and Muhammadu Buhari appeared as factual witnesses.
Obasanjo testified before the tribunal in January 2025, followed by Buhari.
Former Minister of Power Babatunde Fashola and former Minister of Water Resources Suleiman Adamu also appeared as factual witnesses for Nigeria.
Reports from the proceedings indicated that Nigeria’s witnesses challenged the validity of both the original contract and the subsequent 2020 settlement agreement.
Some witnesses listed by Sunrise Power, including Agunloye, reportedly did not appear to adopt their witness statements during the factual-witness hearings.
The arbitration was conducted confidentially, restricting the amount of evidence and arguments that could be publicly disclosed.
The ICC’s ruling in favour of Nigeria now represents a major development in one of the country’s longest-running and most closely watched international commercial disputes.
