Chile is speeding up expansion of its civilian and defense capabilities in Antarctic territory it claims as its own.

Last week Chilean President Sebastian Pinera visited the Latin American nation's installations on the territory, accompanied by Defense Minister Rodrigo Hinzpeter and Foreign Minister Alfredo Moreno, and planted a Chilean flag at the site of a new base on King George Island.

The so-called research station will be operated by the Chilean air force but will also be used by other Chilean military personnel from the army and navy.

Uruguayan President Jose Mujica accompanied Pinera on the trip, which Pinera used in the Chilean media to spotlight Chile's claim on a territory that overlaps with competing claims from Britain and Argentina.

Uruguay has its own base on King George Island on the Fildes Peninsula.

The planned Chilean base will be the closest to the South Pole of all nations, including the United States and China, that have asserted rights to a share of the Antarctic.

Weather warming has given impetus to competing claims.

Chile has unveiled plans for providing easy access to Antarctica for research and tourism from the Chilean mainland at the southernmost tip of South America. Pinera's government has been acquiring defense equipment for the new installations.

The Chilean president's visit to the continent was the third. He marked the site of the new base by placing a Chilean flag, an event given wide publicity in the country.

Pinera has vowed to reinforce Chilean presence on the continent.

"Chile has bases in the Antarctica peninsula but all of them are out of the South Pole circle, so we are considering several alternatives where Chile could make a further penetration into Antarctic territory, with special emphasis in scientific research," Moreno said.

The new base, Chile's fifth in Antarctica, will be near the U.S. and Chinese bases on the King George Island Union Glacier.

The island was first claimed for Britain in 1819, formally annexed as part of the Falkland Islands Dependencies in 1908 but is now a part of the separate British Antarctic Territory. The island was named by British explorer William Smith in 1819.

Chile declared its stake in 1940, as part of the Chilean Antarctic Territory and Argentina in 1943.

The government also wants to expand transport networks at Punta Arenas and Puerto Williams in southern Chile, in an area popular with international expeditions to Antarctica. Chile's plans include facilitating cruise ships sailing to Antarctic points.

Antarctica is about six hours away from Chile's south and current estimates suggest cruise ships can sail from Chile to the frozen continent in three days.

Successive Chilean presidents who visited Antarctica have laid claim to the continent, saying the country's links with Antarctica are rooted in history.

Pinera recently declared that Chile "has always been present in Antarctica with its armed forces and its scientific research institutes."

Similar claims on Antarctica have been made by other countries that signed a 1959 Antarctic Treaty that came into force in 1961. Some of the original restrictions under treaty provisions on militarization and mineral exploitation are being watered down with the passage of time.

The competing territorial claims also threaten to render meaningless the treaty's original intention to avoid conflict.