Arbitral Award Enforcement And The Cross-Jurisdictional Treatment Of Sovereign Immunity

First Tuesday Update is our monthly take on current issues in commercial disputes, international arbitration, and judgment enforcement. In this update, we examine several recent developments in arbitral award recognition litigation against sovereigns that highlight a growing divergence between US courts and courts in other major enforcement jurisdictions. While outcomes generally favor award creditors across jurisdictions (though not always), courts are relying on distinct—and sometimes competing—doctrines to get there. These differences are becoming increasingly consequential for enforcement strategy, particularly in cases involving sovereigns or their agencies and instrumentalities. At the same time, recent decisions – including the Second Circuit's ruling in Petersen v. Argentina – underscore that some US courts continue to accord substantial weight to sovereign immunity and related defenses.

We look at several recent decisions from courts in the United States, the United Kingdom, Australia, and Canada. As a practical matter, these jurisdictions are often viewed as strong enforcement forums, but they do not take uniform approaches as to whether—and how—sovereign immunity may bar recognition of arbitral awards. These various approaches can have practical impacts on where you enforce, and how you plead the case to overcome immunity.

In the United States, enforcement turns on the Foreign Sovereign Immunities Act (FSIA). Outside the United States, courts tend to rely more heavily on doctrines of implied waiver, consent, and comity grounded in public international law. Over the past several months, a series of high‑profile decisions abroad relied on these doctrines to find exceptions to sovereign immunity—even as the US Supreme Court declined to assess the contours of implicit waiver in a case involving Zimbabwe.

US courts treat international arbitral award enforcement primarily as a statutory exercise. Under the FSIA, a foreign sovereign that agrees to arbitrate disputes falling under the Convention is deemed to have waived immunity from suit under the Act's arbitration exception, 28 U.S.C. § 1605(a)(6). Courts applying that framework generally decline to revisit questions of international public policy, foreign constitutional constraints, or regional treaty regimes.

Recent enforcement proceedings arising out of the long‑running Micula litigation illustrate this analytical approach. In the US District Court for the District of Columbia, Micula v. Government of Romania, No. 17-CV-02332 (APM) (DDC), the creditor has been successful in having its Energy Charter Treaty award recognized against Romania, notwithstanding Romania's (and the EU's) claims that recognition violates EU law. This issue has been the subject of litigation in UK and European courts as . In the United Kingdom, the Miculas succeeded in enforcing their ICSID award against Romania after the UK Supreme Court lifted a stay on enforcement in 2020, holding that the UK's obligations under the ICSID Convention could not be displaced by EU rules. Although the Court of Justice of the European Union later held in Commission v. United Kingdom (C‑516/22) that the UK Supreme Court's decision violated EU law, that ruling did not disturb the UK judgment itself and underscored the clash between EU law and international arbitral enforcement mechanisms. By contrast, within the European Union, courts have repeatedly refused to permit payment or enforcement of the Micula award on the ground that satisfaction of the award would constitute unlawful State aid, most recently with the EU General Court confirming that execution of the award is incompatible with EU law.

In April 2026, the DC Court imposed an additional $5.8 million in contempt sanctions against Romania for ongoing non‑compliance with post‑judgment discovery orders, emphasizing that Romania's continued reliance on EU‑law objections was not a valid basis for resisting enforcement or discovery under US law. Micula, No. 17-CV-02332, ECF No. 242 (April 14, 2026). To date, Romania owes a total of $21 million in sanctions.

A similar dynamic played out in enforcement proceedings against Spain in NextEra Energy Global Holdings B.V. v. Kingdom of Spain, 112 F.4th 1088 (D.C. Cir. 2024). There, the DC Circuit held that US courts have jurisdiction under the FSIA's arbitration exception to enforce investor‑State awards rendered under the Energy Charter Treaty, rejecting Spain's argument that EU law—particularly the Achmea and Komstroy decisions—negated Spain's consent to arbitrate or its waiver of immunity. Spain sought cert, supported by several EU Member States and the European Commission as amicus, but the Court denied certiorari, leaving in place the DC Circuit's refusal to import EU law limitations into US arbitral award enforcement analysis.

While outcomes regarding international arbitration enforcement in the United Kingdom often align with those in the United States, the analytical framework is different. In March 2026, the UK Supreme Court held in Kingdom of Spain v. Infrastructure Services Luxembourg S.à.r.l. and Republic of Zimbabwe v. Border Timbers Ltd. that sovereign immunity does not prevent the registration of ICSID awards in England and Wales. The court emphasized the distinction between recognition (or registration) and execution, holding that immunity defenses are generally unavailable at the threshold stage when a state has consented to arbitration by treaty. Notably, the UK Supreme Court rooted its analysis in international law principles of consent and waiver rather than in any statutory analogue to the FSIA. The result—facilitating recognition while preserving immunity at the execution stage—closely mirrors US outcomes but reflects a more discretionary, common‑law conception of sovereign consent.

Canada has taken a similar doctrinal path in Republic of India v. CCDM Holdings. The Quebec Court of Appeal held that India had expressly waived its jurisdictional immunity by necessary implication through its agreement to international arbitration under the India–Mauritius BIT and its ratification of the New York Convention. Although the Convention contains no express reference to sovereign immunity, the court concluded that India's consent to treaty arbitration and its Convention commitments amounted to an explicit submission to Canadian jurisdiction under the State Immunity Act. This reasoning—grounded in international arbitration practice and public international law—aligns more closely with recent UK authority than with the approach taken by courts in the United States.

The UK and Canada's approach stands in contrast with the position recently taken by the High Court of Australia in CCDM Holdings LLC v. Republic of India [2026] HCA 9 (the same underlying dispute as what was addressed by the Canada court). In that case, the court unanimously held that a State's ratification of the New York Convention does not, standing alone, constitute a waiver of sovereign immunity. Emphasizing that any waiver must be “clear and unmistakable,” the court rejected arguments that Article III of the Convention implicitly displaces domestic immunity rules. Australia's approach closely resembles that of the United States, where courts likewise require an independent statutory or contractual basis for jurisdiction and do not treat the Convention itself as a waiver of immunity.

Against that backdrop, the Supreme Court recently declined to intervene in the debate in Amaplat Mauritius Ltd. v. Zimbabwe Mining Development Corp.—and decide whether, when a foreign sovereign that is a party to the New York Convention agrees to arbitrate a dispute governed by the Convention, it impliedly waives immunity from an action in US courts to recognize a valid foreign judgment confirming the arbitral award in another member state. This stands in contrast to the Canadian court judgment recognizing the same judgment and arbitral award sued on in the U.S. Amaplat Mauritius Ltd. v. Zimbabwe Mining Development Corp., Case No. CV-22-0068479200CL (Can. Ont. Super. Ct. J., June 30, 2025). 

In Amaplat, the US District Court for the District of Columbia held that Zimbabwe had implicitly waived immunity by agreeing to arbitrate and by ratifying the New York Convention, thereby permitting recognition of a Zambian court judgment that had confirmed the arbitral award. The DC Circuit reversed, holding that neither the FSIA's arbitration exception nor its implied‑waiver provision extended to actions seeking recognition of foreign court judgments—even those confirming Convention awards—and expressly declined to follow contrary authority from the Second Circuit, see Seetransport Wiking Trader Schiffarhtsgesellschaft MBH & Co., Kommanditgesellschaft v. Navimpex Centrala Navalathereby creating a circuit split. The case attracted significant amicus interest at the Supreme Court, which nevertheless denied certiorari in April 2026, leaving the DC Circuit's formal distinction between arbitral awards and foreign judgments in place.

In addition, the United States has to date followed a different path than most other jurisdictions in recognizing ICSID awards. Following the Mobil Cerro Negro, Ltd. v. Bolivarian Republic of Venezuela, 863 F.3d 96 (2d Cir. 2017) decision from the Second Circuit, US courts require the filing of a plenary action, with service of process, venue, and personal jurisdiction to recognizing an ICSID award, whereas most other countries follow a summary procedure.

Given these different jurisdictional approaches in leading enforcement jurisdictions, parties should be aware of the various claims and defenses available: 

• In the United States and Australia, enforcement must be built around the statutory text, with close attention to following all of the enumerated requirements.
• In jurisdictions such as the UK and Canada, courts may engage more openly with international law concepts of consent and waiver—sometimes allowing for earlier recognition but reserving broader discretion at the execution stage.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.