Four British oil companies carrying out exploration work in waters near the Falkland Islands have been barred from operating in Argentina.

The measure affects Borders & Southern Petroleum, Desire Petroleum, Argos Resources and Falkland Oil and Gas.

All four are prohibited from working in the South American nation for 20 years due to their unauthorized exploration activity "in areas near the Malvinas Islands (as the Falklands are known to Latin Americans)," the Argentine government said in a statement posted Friday on its Web site.

The resolution says the four companies violated Argentine law governing oil exploration and production by carrying out activities in that offshore sector without the government's permission.

Argentine authorities said the oil firms were operating under an "illegitimate license to explore for oil and gas in areas near the Malvinas that was granted by the illegitimate government that controls those islands."

The oil companies were notified of their situation in March 2012, according to the Argentine government.

Buenos Aires informed them of its firm intention to take all legal and administrative action at its disposal to "defend its rights."

In May 2012, Argentina's Energy Secretariat declared the activities of these companies in waters near the Malvinas to be "illegal and clandestine."

The South Atlantic archipelago was the object of a brief war in the early 1980s pitting Argentina against Britain.

Argentine troops invaded the Falklands on April 2, 1982, at the order of the military junta then in power in Buenos Aires.

Full-fledged fighting officially began on May 1, 1982, with the arrival of a British task force, and ended 45 days later with the surrender of the Argentines.

The conflict claimed nearly 1,000 lives - some 700 Argentines and 255 British soldiers and sailors.

Buenos Aires demands that Britain comply with a 1965 United Nations resolution describing London's control of the Falklands - which dates from 1833 - as colonialism and calling on the parties to resolve the dispute through dialogue.

London has refused to discuss the question of sovereignty and says the Falklanders should decide their own future. EFE