Argentina's president has threatened to launch a legal challenge against the British government unless it halts oil exploration work off the coast of the Falkland Islands.
In a social media post, President Javier Milei set a two‑week deadline for the Sea Lion oilfield project, a joint venture between Israeli and British companies, to be scrapped.
The companies insist they have valid licences issued by Britain.
His remarks heighten tensions between the UK and Argentina over sovereignty of the archipelago, known in Argentina as Las Malvinas, more than 40 years after the 1982 Falklands War.
Milei said that if the deadline was not met, he had "instructed the Foreign Ministry and legal teams to initiate international arbitration" against the UK over the project.
He warned that if the "illegitimate exploitation" did not end within two weeks, Argentina would bring the matter before the International Tribunal for the Law of the Sea in Hamburg.
The tribunal is an independent judicial body responsible for applying the United Nations Convention on the Law of the Sea.
The move follows Milei’s criticism of the UN for failing to act over Falkland sovereignty, calling it a "useless organisation".
Since then, UK Defence Secretary Wes Streeting said Argentina "lacks the ability" to seize the Falklands by force.
Milei previously described the Sea Lion oilfield as a "clear and present danger". The field lies about 130 miles (209 km) from the Falkland Islands and contains an estimated 1.7 billion barrels of oil. British Rockhopper Exploration and Israeli Navitas Petroleum plan to begin extraction within two years, claiming they hold valid licences.
The islands voted overwhelmingly to remain a British overseas territory in a 2013 referendum, with 99.8% in favour. The 1982 conflict ended with Britain ejecting Argentine forces after a 74‑day war, causing 255 British military deaths, 3 islanders, and 649 Argentine military casualties.
