The Federal Government has emerged victorious in a nearly nine-year international arbitration dispute against Sunrise Power and Transmission Company Limited over the long-delayed 1,500MW Mambilla Hydroelectric Power Project, defeating claims that had put Nigeria’s potential exposure at more than $3.38 billion.

The project was originally conceived as a 3,050-megawatt hydroelectric plant in Taraba State, but the Federal Government later scaled down the planned capacity by about 50 per cent to 1,525MW, before further rescoping it to roughly 1,500MW in order to make it financially viable and “bankable” for lenders.

President Bola Tinubu confirmed the victory in a State House statement on Thursday, disclosing that an International Arbitration Tribunal, operating under the auspices of the International Chamber of Commerce in Paris, France, had issued an award in Nigeria’s favour and dismissed Sunrise’s claims.

The arbitration dispute traces back to October 10, 2017, when Sunrise commenced proceedings against Nigeria at the ICC International Court of Arbitration, alleging a breach of a 2003 agreement concerning the development of the Mambilla power project.

According to the Presidency, Sunrise had demanded $680 million as a settlement sum plus interest in the latest arbitration, related to a separate case in which it is claiming more than $2.7 billion in compensation and interest over disputes tied to the development of the Mambilla project in Taraba State.

Taken together, the two related claims placed Nigeria’s potential exposure at more than $3.38 billion.

The final award, issued on September 17, 2026, came nearly nine years after the company first initiated arbitration proceedings against the Federal Government.

Tinubu said the ruling had cleared a major obstacle that had long stalled progress on the multibillion-dollar power project. “Today’s ICC ruling clears the single biggest legal hurdle that has paralysed the Mambilla hydro power project for years,” the President said.

Details of the award, earlier reported by TheCable, showed that the three-member tribunal dismissed Sunrise’s claim for a declaration that Nigeria had breached its contractual obligations under a settlement agreement and an addendum entered into by the parties.

The tribunal also rejected the company’s request for an order compelling Nigeria to pay $400 million, made up of a $200 million settlement sum and another $200 million claimed as a default payment.

According to the report, the tribunal further declared that Sunrise promoter, Leno Adesanya, was bound by the arbitration agreement with Nigeria under the settlement agreement and addendum.

It consequently held that it had jurisdiction over Nigeria’s counterclaim against Adesanya and Sunrise, and ordered Sunrise and Adesanya to reimburse Nigeria for 75 per cent of the legal fees and expenses incurred by the country in defending the arbitration.

Nigeria’s legal fees were put at $11.82 million, of which $2.5 million is expected to be covered directly from funds held in escrow by the ICC and released upon notification of the final award.

Sunrise and Adesanya were ordered to pay the outstanding $9.32 million, along with interest at an annual rate of 10 per cent, compounded annually from the date of notification of the final award until the amount is fully settled.

The arbitration costs were fixed at $1.66 million, with Sunrise and Adesanya expected to bear 75 per cent while Nigeria would cover the remaining 25 per cent.

TheCable identified the three members of the tribunal as Melaine van Leeuwen, who presided over the panel, alongside Stavros Brekoulakis and Simon Nesbitt as co-arbitrators.

Nigeria was represented by a legal team led by Elizabeth Oger-Gross and Tolu Obamuroh of Paul Hastings LLP.

Tinubu commended the Attorney-General of the Federation and Minister of Justice, Lateef Fagbemi, along with officials of the Federal Ministry of Justice, for their handling of the dispute.

He also praised the country’s legal team for what he described as its professional defence of Nigeria’s interests.

“This latest decision affirms the Nigerian State’s determination not to succumb to predatory and exploitative claims by corrupt local and international entities and their enablers and funders,” Tinubu said.

The President also paid tribute to former President Olusegun Obasanjo and the late former President Muhammadu Buhari, both of whom testified in Nigeria’s defence during the arbitration proceedings.

“I commend the patriotism and support of former President Olusegun Obasanjo, GCFR, and late President Muhammadu Buhari, GCFR, who testified in the case, which dated back to an illegal 2003 contract to build a 3,050-megawatt hydroelectric plant in Taraba State under a build-operate-transfer model. The Federal Executive Council never authorised the contract,” he said.

Tinubu also acknowledged former ministers Babatunde Fashola and Suleiman Adamu, who participated as witnesses in the case, along with other experts involved in Nigeria’s defence.

He further commended the National Security Adviser for supporting the government’s case and the Economic and Financial Crimes Commission for its investigation into the dispute.

The dispute has its roots in an agreement reached more than two decades ago concerning the proposed development of the Mambilla power project, with the 2003 contract providing for the construction of a 3,050-megawatt hydroelectric plant in Taraba State under a build-operate-transfer model.

In 2016, then Minister of Power, Works and Housing, Babatunde Fashola, had described the project as one that would generate about 3,000MW.

However, in February 2021, then Minister of Power, Saleh Mamman, announced that the Federal Government had revised the planned capacity downward by 50 per cent, from 3,050MW to about 1,525MW.

The stated reason for the revision was to cut the project’s cost by about $1 billion and make it more financially viable.

In July 2021, Mamman told the Senate Committee on Power that the project had subsequently been rescoped to 1,500MW to make it “bankable” and acceptable to lenders.

He explained that the original 3,050MW capacity was no longer considered financially viable under prevailing market conditions.

The original project was estimated to cost between $5 billion and $5.8 billion, while the rescoped version, at roughly 1,500 to 1,525MW, was reported to cost about $4 billion.

The parties had subsequently attempted to resolve the dispute through a settlement agreement in 2020.

However, disagreement over the implementation of that settlement led to further arbitration, with Sunrise seeking payment from the Federal Government over an alleged failure to honour the agreement.

The Mambilla project itself has remained largely on the drawing board despite successive administrations identifying it as a major component of efforts to boost Nigeria’s electricity generation capacity.

The project has suffered repeated setbacks arising from legal disputes, financing challenges and changes to its implementation arrangements.

A Federal Ministry of Power implementation document had identified the arbitration, the completion of financing arrangements with the Export-Import Bank of China, and the need to re-scope the project as among the key challenges affecting its execution.

In the latest development, Tinubu said the government would continue to honour legitimate contractual obligations and work with genuine investors, while defending the country against claims it considered unjustified.

“I want to assure you that while our country remains committed to partnering with genuine investors and honouring its legal obligations, it will continue to defend all opportunistic claims instituted against our commonwealth strongly,” the President said.

The arbitration victory also comes against the backdrop of Nigeria’s ongoing efforts to defend itself against multibillion-dollar international claims arising from disputed government contracts.

In 2023, Nigeria recorded another major legal victory when a United Kingdom court set aside an $11 billion arbitration award obtained by Process & Industrial Developments Limited over a failed gas processing agreement.

The PUNCH earlier reported that Justice James Omotosho of the Federal High Court sentenced former Minister of Power, Saleh Mamman, to 75 years’ imprisonment in absentia over a N33.8 billion money laundering and fraud case instituted by the Economic and Financial Crimes Commission.

Omotosho further directed Mamman to refund the outstanding balance from the N22 billion the prosecution established was diverted from funds meant for the Mambilla and Zungeru hydroelectric power projects.

Former Minister of Power, Prof. Barth Nnaji, recently offered an assessment of Nigeria’s power sector, attributing over a decade of stalled investment to policy inconsistency, weak infrastructure development, and the abrupt discontinuation of a financing framework that had begun attracting global capital into electricity generation projects.

Nnaji spoke in Lagos at the 2026 conference of the Nigerian Association for Energy Economics, where he addressed participants on the future of Nigeria’s energy mix, the role of natural gas in powering the economy, the financing bottlenecks facing major projects, and the long-standing delays surrounding strategic assets such as the Mambilla hydropower project.

Nnaji regretted that Nigeria has gone 11 years without financing any new major power plant, a situation he traced directly to the dismantling of a government-backed financing support mechanism introduced during his tenure as minister.

Expanding beyond the financing challenge, Nnaji argued that Nigeria must adopt a realistic and pragmatic view of energy transition, especially in light of recent global developments.