President Javier Milei formally submitted legislation to Argentina's Congress on Wednesday to sharpen sanctions against companies operating in the Falkland Islands under British authorisation. The bill targets firms engaged in hydrocarbon exploration and fishing around the archipelago.

Argentina claims sovereignty over the islands it calls the Malvinas, which Britain has administered since a brief 1982 war. The proposed measures would expand existing penalties, barring sanctioned companies and their executives from operating in Argentine territory and from accessing the country's financial system.

The move follows Milei's announcement earlier this week that he intended to strengthen the legal framework against what Buenos Aires regards as illegal exploitation of natural resources in disputed waters. Argentine government officials said the bill responds to renewed oil exploration licences granted by the Falklands government.

The legislation risks straining relations with London at a time when Milei has cultivated close ties with Western governments. The British Foreign Office has consistently rejected Argentine sovereignty claims, citing the islanders' right to self-determination affirmed in a 2013 referendum.

A spokesperson for the Argentine foreign ministry said the bill reaffirmed the country's "permanent and inalienable" claim, while stressing Buenos Aires remained committed to a peaceful resolution through dialogue.