Argentina has instructed its Foreign Ministry and government legal teams to initiate international arbitration against the United Kingdom over hydrocarbon activities in the Malvinas Islands, President Javier Milei announced on September 28. The dispute centres on the Sea Lion oil project in the North Malvinas Basin, which Buenos Aires describes as an unauthorised exploitation of Argentine resources.
Milei said Argentina would proceed under Annex VII of the United Nations Convention on the Law of the Sea. The Argentine government said the proceedings are intended to block hydrocarbon exploitation through the Sea Lion project and address any other measures it considers capable of aggravating the dispute.
“If in two weeks the United Kingdom does not halt the illegitimate exploitation, we will go to the International Tribunal for the Law of the Sea,” the government said. Milei made the announcement at an event commemorating the 44th anniversary of the Malvinas War.
In an official statement, the President’s Office said unilateral exploitation of natural resources in the Malvinas Islands, South Georgia and the South Sandwich Islands, and their surrounding maritime spaces, “is contrary to international law”. It also said such activity causes “irreversible and irreparable harm” to sovereignty rights claimed by Argentina.
The Argentine government cited UN General Assembly Resolution 2065, which recognises the existence of a sovereignty dispute between Argentina and the United Kingdom and calls on the two governments to seek a peaceful settlement through negotiations. Buenos Aires also referred to Resolution 31/49, which calls on both sides to refrain from decisions that would imply unilateral modifications while the UN-recommended process continues.
The announcement was accompanied by new measures against Thales UK Limited. According to the Argentine government, it had detected operations involving a British-registered aircraft flying between the Malvinas Islands and Punta Arenas, Chile, without Argentine authorisation. Milei ordered the “urgent” initiation of sanctions proceedings, criminal complaints and diplomatic actions over the flights.
The latest measures add to a series of actions by Buenos Aires against companies involved in the Sea Lion project, which is led by Navitas Petroleum and Rockhopper Exploration. In early September, Argentina initiated sanctions proceedings against companies and suppliers linked to what it considers unauthorised hydrocarbon activities and filed a criminal complaint against the companies involved.
Milei has continued to press the Malvinas sovereignty dispute through diplomatic and legal channels. During his address to the United Nations General Assembly earlier this month, he called on Britain to resume negotiations over sovereignty of the islands and warned that Argentina would take action against companies exploiting resources without authorisation from Buenos Aires.
The government’s latest announcement therefore places the Sea Lion project at the centre of a new phase in the dispute, with Argentina preparing potential proceedings under the UN Convention on the Law of the Sea while maintaining its demand for negotiations over sovereignty.
In his statement, Milei framed the move as part of his government’s broader claim over the islands, declaring: “Malvinas are Argentinean and defend themselves with deeds, not words.”
