(CNN) -- Argentine President Cristina Fernandez de Kirchner signed a decree Tuesday requiring all ships navigating from Argentina to the disputed Falkland Islands to carry a government permit. The move comes as tensions over the territory simmer because of British oil companies' efforts to drill off the northern coast of the islands. The Falklands, known as Las Malvinas in Argentina, lie in the South Atlantic Ocean off the Argentinean coast and have been under British rule since 1833. But Argentina has always claimed sovereignty over them. The two nations fought a war over the islands in 1982. Tuesday's decree followed an accusation made last week by the Argentine government that a ship docked on the mainland was preparing to transport tubes to the Falklands for oil and gas exploration.
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Argentina requires ships navigating from Argentina to the Falklands to carry permit
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Tensions over islands because of UK oil firm's efforts to drill off the coast of the islands
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Argentina claims ship docked on mainland was to transport tubes for Falklands oil exploration
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Falklands under British rule since 1833, but Argentina claims sovereignty over them
The Argentine position is that natural resources around the islands should be protected, and @placeholder must accept international resolutions labeling the Falklands a disputed area.