Argentina on Monday announced a formal criminal complaint against several international energy companies for drilling for oil and gas under British licenses near the Falkland Islands, which Buenos Aires calls Islas Malvinas.

Argentine Foreign Minister Pablo Quirno, backed by Treasury Attorney General Sebastian Amerio, filed the complaint in federal court against Israel-based Navitas Petroleum, Canada’s JHI Associates and Eco Atlantic Oil and Gas. The government is also targeting individual directors, managers and shareholders, accusing them of carrying out unauthorized hydrocarbon, oil and natural gas exploration in the North Malvinas Basin.

Argentine President Javier Milei’s office said the legal action is a “concrete action to protect natural resources and safeguard the sovereignty” of Argentina.

Read: Argentina’s Milei steps up Falklands sovereignty claims with oil sanctions

The long-standing sovereignty dispute over the Falkland Islands, a British-controlled archipelago situated about 483 kilometres (300 miles) east of the Argentine coast, has flared recently as offshore drilling projects move toward production. Buenos Aires argues that Britain has illegally occupied the islands since 1833.

As part of a broader defensive policy, Milei also signed a directive instructing Economy Minister Luis Andres Caputo to prioritise funding for an integrated naval base, a strategic military facility designed to support maritime security and territorial defence.

The complaint follows separate sanction proceedings initiated by Argentina on Friday against 45 individuals and entities. Milei previously warned that the Sea Lion oil project, an offshore drilling venture, poses an imminent threat to national resources. While London has dismissed these legal threats as domestic politics, the foreign companies said they plan to proceed with drilling under UK licenses.