Argentina’s President Cristina Fernandez de Kirchner has renewed calls for the UK to return the Falkland Islands, which remain at the center of a longstanding territorial dispute between the two countries.

Fernandez wrote in an open letter to British Prime Minister David Cameron that the Falklands, known as Las Malvinas in Argentina, were colonized by the UK 180 years ago and should be returned.

"The Argentines on the Islands were expelled by the Royal Navy, and the United Kingdom subsequently began a population implantation process similar to that applied to other territories under colonial rule,” she said in the letter, which was also copied to U.N. Secretary-General Ban Ki-moon, CNN reported.

"Since then, Britain, the colonial power, has refused to return the territories to the Argentine Republic, thus preventing it from restoring its territorial integrity."

Fernandez cited a 1965 U.N. resolution, calling on the two countries to resolve the dispute, though Cameron has refused to engage in bilateral talks, emphasizing the rights of the Falkland Islanders to determine their sovereignty.

"Unlike the government of Argentina, the United Kingdom respects the right of our people to determine our own affairs, a right that is enshrined in the U.N. Charter and which is ignored by Argentina," Cameron said, according to the BBC.

"There are three parties to this debate, not just two as Argentina likes to pretend,” he added. "The islanders can't just be written out of history."

Argentina went to war with Britain over the islands in 1982, occupying them for more than two months until suffering defeat by a British naval expeditionary force. There were 649 deaths on the Argentine side and 255 on Britain’s.

The Falkland Islands became a British overseas territory after the colonial period -- which the UK Foreign Office claims extends back to 1765 and conflicts with Fernandez’s 1823 date -- and continues to receive British military support.

Residents of the Falkland Islands, currently a population of roughly 3,000, have scheduled a referendum in March that will determine their position on the territory’s sovereignty.

Cameron expressed his support for the referendum in response to Fernandez’s letter.

"The future of the Falkland Islands should be determined by the Falkland Islanders themselves -- the people who live there," Cameron said, the BBC reported.

"They're holding a referendum this year, and I hope the president of Argentina will listen to that referendum and recognize it is for the Falkland Islanders to choose their future, and, as long as they choose to stay with the United Kingdom, they have my 100 percent backing," he added.