Public hearings opened in Hamburg on Tuesday 10 November in Argentina's legal challenge to the United Kingdom over the Sea Lion oil project north of the Falkland Islands, in a case that will test whether a maritime tribunal can intervene in a dispute tied to sovereignty.

The International Tribunal for the Law of the Sea will hear two days of arguments, on 10 and 11 November, on Argentina's request for provisional measures against the UK. The case is listed as Case No. 37, the Case concerning hydrocarbon exploitation in the South-West Atlantic Ocean (Argentina v. United Kingdom).

What Argentina is asking for

Argentina lodged its request on 13 October under Article 290, paragraph 5, of the United Nations Convention on the Law of the Sea, which allows the tribunal to act before the arbitral tribunal that will ultimately decide the dispute has been constituted. That arbitral tribunal does not yet exist.

Buenos Aires is asking the tribunal to order the UK to prevent the start or continuation of hydrocarbon exploitation by the Sea Lion project, to issue no further licences on the disputed continental shelf, to refrain from using information gathered during exploration, and to protect the marine environment in the area. The hearings are open to the public and are being broadcast live on the tribunal's website.

The project at the centre of the case

Sea Lion sits about 200 kilometres north of the Falkland Islands and is operated by Israel's Navitas Petroleum, which holds 65 percent, with Britain's Rockhopper Exploration holding the rest. The partners took their final investment decision in December 2025 and plan first production in March 2028, with drilling currently scheduled to begin in January 2027.

The licences cover an area of about 541 square kilometres, roughly 107 nautical miles north of the islands. The project has become the focus of the long-running dispute between the UK, which administers the islands, and Argentina, which claims sovereignty over them and calls them the Malvinas.

The jurisdiction question

The central legal issue is whether the tribunal can consider Argentina's maritime claims without first resolving the underlying sovereignty dispute. The tribunal can determine disputes about the interpretation or application of the Law of the Sea convention, but it does not decide territorial sovereignty under general international law.

Legal experts have said Argentina's claim could fall at the first hurdle on jurisdiction, and the tribunal is expected to consider that question before any ruling on the project itself. A decision on the provisional measures request is expected soon after the hearings conclude.

Argentina has already taken domestic steps against the project. On 16 September an Argentine federal court ordered the project suspended, and on 8 September Argentina's foreign minister filed a criminal complaint against Navitas entities and other firms under a 2011 law barring participation in unauthorised hydrocarbon activity on the Argentine continental shelf. The UK has rejected Argentina's claims and does not recognise Argentine jurisdiction over the islands.