Britain Tuesday warned South American countries against continuing their "economic blockade" against the Falkland Islands, under which ships from the disputed islands are blocked from entering the South American ports, according to dpa. In a written statement to parliament, Foreign Secretary William Hague said Britain was "happy" with the decision of Brazil, Chile and Uruguay to allow Falkland Island ships to enter their ports, providing they bore another national flag or the Red Ensign, which is the UK's civil ensign. Their conduct was the result of "productive and honest discussions" held recently with the nations concerned, said Hague. However, he criticized Paraguay and Argentina for refusing to grant Falkland ships entry to their ports just before the New Year, saying that their behavior was "inconsistent" with the principles of the United Nations charter. The British government would always ensure that the Falkland Islanders' right to determine their political future was respected, he added. In 1982, former British prime minister Margaret Thatcher went toward with Argentina over the sovereignty of the Falkland Islands in the South Atlantic. Despite surrendering to Britain after several weeks of fighting, Argentina continues to claim the islands.