ICSID Arbitration: state immunity

Kingdom of Spain v Infrastructure Services Luxembourg Sarl and Another; Republic of Zimbabwe v Border Timbers Ltd and Another [2026] UKSC 9; [2026] 1 Lloyd's Rep 319 was an appeal from the decision of the Court of Appeal [2025] 1 Lloyd's Rep 66, itself a combined appeal against first instance decisions of Fraser J ([2023] 2 Lloyd's Rep 299) and Dias J ([2024] 1 Lloyd's Rep 427) respectively. The cases both raised the question of the relationship between the Washington Convention on the Settlement of Investment Disputes between States and Nationals of Other States 1965 (ICSID) and sovereign immunity under the State Immunity Act 1978.

The first instance decisions took quite different views of that relationship, although each concluded that a contracting state could not rely upon sovereign immunity. The Court of Appeal and the Supreme Court were concerned only with immunity defences: the Zimbabwe case involved other defences and these were not up for determination in the present hearing.