Public international law

Representative matters

• The Federal Republic of Somalia before the ICJ in advisory proceedings to determine whether the right to strike is protected under international law. The case stems from a request from the Governing Body of the International Labor Organization, which requested an advisory opinion on whether the Freedom of Association and Protection of the Right to Organize Convention, 1948 (No. 87) includes the right to strike.
• The Republic of Djibouti before the ITLOS in advisory proceedings concerning the obligations of States in respect of climate change. In an advisory opinion issued in May 2024, the ICJ held that States party to UN Convention on the Law of the Sea must take measures to prevent marine pollution caused by climate change, in addition to their obligations under the Paris Agreement.  
• The Republic of Djibouti in relation to an advisory opinion before the ICJ concerning the obligations of States in respect of climate change.  In July 2025, the ICJ’s landmark Advisory Opinion found that States have binding legal obligations under international law to address climate change and protect the environment.
• A leading international bank in LCIA arbitration and English court proceedings arising from the close out of a swap transaction with the Central Bank of Venezuela ("BCV"), following the BCV being placed on OFAC’s sanctions list. Issues raised include sovereign immunity, immunity waiver clauses, the “act of state” doctrine and contested claims from rival factions, linked to the wider issue of recognition of the Venezuelan head of State.

• The Kingdom of Bahrain in its defence of a pending ICSID arbitration concerning the intersection of investment treaty obligations and international law sanctions against the Islamic Republic of Iran.
• The Grand Duchy of Luxembourg in its defence of investment treaty claims of more than USD 15 billion in connection with EU sanctions imposed against Mikhail Friedman following Russia’s invasion of Ukraine. This is the first known investment treaty case to challenge the entire EU sanctions regime.  
• The Republic of Panama as a petitioner and counter-defendant in an action to enforce an ICSID Award brought against the award debtor in the U.S. District Court for the Southern District of Florida. The case challenges the summary nature of proceedings to enforce ICSID arbitration awards and raises significant questions of foreign sovereign immunity.
• NextEra Energy Global Holdings B.V. and NextEra Energy Spain Holdings B.V., as holders an arbitration award of more than EUR 300 million against the Kingdom of Spain, on the enforcement of the award in the UK, United States and other jurisdictions. In February 2026, NextEra achieved a significant victory in the Singapore High Court (represented by TSMP Law, instructed by A&O Shearman), where it obtained the first-ever judgment upholding registration of an ICSID award in Singapore. The High Court rejected Spain’s invocation of sovereign immunity.  
• The Republic of Cuba on its challenge, brought at the World Trade Organization, to Australia’s Tobacco Plain Packaging Act 2011. This was the first time that Cuba had challenged another country’s commercial legislation at the World Trade Organization.