Nigeria has secured an arbitration victory in its long-running dispute with Sunrise Power and Transmission Company over the proposed Mambilla Hydroelectric Power Project in Taraba State. An International Chamber of Commerce tribunal in Paris issued its award on Thursday, 17 September 2026, rejecting claims tied to a settlement agreement and addendum, according to the presidency and Nigerian news organisations that reviewed or reported the decision.
The tribunal rejected Sunrise's request for a declaration that Nigeria breached the settlement documents and refused an order requiring the government to pay $400 million, described in the award reporting as a $200 million settlement sum and a further $200 million default sum. It also held that promoter Leno Adesanya was bound by the arbitration agreement and that the panel had jurisdiction over Nigeria's counterclaim against him and the company.
What the tribunal decided
Costs were also awarded substantially in Nigeria's favour. The panel ordered Sunrise and Adesanya to reimburse 75% of Nigeria's reported $11,819,506.51 legal fees and expenses. Of that amount, $2.5 million is to come from funds held in escrow, while the reported balance of $9,319,506.51 is payable with annual interest of 10%, compounded from notification of the final award until payment.
The tribunal fixed the arbitration's institutional and panel costs at $1,656,500, allocating 75% to Sunrise and Adesanya and 25% to Nigeria. Those orders are legal findings and payment directions; public reporting had not established that the outstanding sums had already been collected when this article was published.
Dollar figures in early headlines differ because the dispute has involved more than one claim and more than one stage. TheCable described a 2017 arbitration in which Sunrise sought $2.354 billion over an alleged breach connected to a disputed 2003 agreement, followed by a second arbitration concerning the 2020 settlement. President Bola Tinubu's statement said Sunrise sought $680 million including interest in the latest matter while pursuing more than $2.7 billion in another arbitration.
Why different reports use different dollar figures
The published decision details reported by TheCable focus on the settlement-related request for $400 million. For that reason, this report does not collapse every figure into a single award or claim. The confirmed development is that the 17 September tribunal rejected the claims before it and shifted most of the legal and arbitration costs to Sunrise and Adesanya.
The underlying project has been disputed for more than two decades. Sunrise's case traced back to a 2003 build-operate-transfer arrangement for a 3,050-megawatt plant. The Nigerian government has maintained that the Federal Executive Council did not authorise that contract. The larger Mambilla scheme has subsequently been described by the government as a proposed 3,960MW project in Taraba State.
President Tinubu called the award the removal of the project's biggest legal hurdle and commended the federal legal team. That assessment is a government position about the significance of the ruling. It does not itself establish a new engineering design, financing close, procurement award, environmental approval, construction start date or commissioning schedule.
A legal victory is not a construction timetable
Mambilla has repeatedly been presented as a potentially transformative source of electricity, but the project's history shows why legal clearance and physical delivery must be reported separately. A dam of this scale would still require credible financing, updated technical and environmental work, contracts capable of surviving scrutiny, resettlement and community safeguards, transmission planning and transparent milestones.
The immediate result is therefore substantial but narrower than a completed power project: Nigeria has defeated the settlement-related claims reported in this ICC award and obtained a costs order. The next evidence to watch is whether the parties comply with the financial directions, whether any challenge or enforcement proceeding is announced, and whether the government publishes a funded, independently verifiable plan to move Mambilla from litigation into lawful construction.
