LONDON The government plans to submit a claim to the United Nations to extend its Antarctic territory by a million square kilometres, the foreign office said on Wednesday.
The claim is one of five territorial requests planned by Britain ahead of a May 2009 deadline and covers a vast area of the seabed around British Antarctica near the south pole, a spokeswoman said.
"We are one of many coastal states who are submitting various claims," she told Reuters.
She said the four other claims would be for Atlantic seabed territory around South Georgia and the Falkland Islands and also around Ascension Island in the South Atlantic, near the Bay of Biscay in the North Atlantic, and in the Hatton-Rockall basin off Scotland's coast.
The claim to extend British sovereignty in Antarctica could spark disputes with South American nations such as Argentina and Chile.
Argentine Foreign Minister Jorge Taiana said his country was working on its own presentation to the United Nations.
This would cover the Antarctic as well as South Georgia and the Falkland Islands, called Malvinas by Argentina, which claims the islands and fought a 10-week war to try to wrest them from British control in 1982.
"In defence of our national interest and our legitimate sovereign rights we are intensely working on our presentation," Taiana told reporters in Rome.
The British claim also conflicts with the spirit of 1959 Antarctic Treaty, to which Britain is a signatory, which prevents all exploitation of oil gas and minerals, other than for scientific research.
But the foreign office spokeswoman said that because of the Treaty, Britain's claim would be "theoretical" for the moment.
"It's incredibly unlikely that the Antarctic Treaty would ever be abolished," she said. "But in order to safeguard our interests for the future, we are submitting a claim."
May 13, 2009 marks a deadline for states to stake their claims in what some experts are describing as the last big carve-up of maritime territory in history.
Around 7 million sq km (2.7 million sq miles) -- the size of Australia -- could be divided between nations around the world -- territory which could hold unknown riches ranging from oil and gas to seabed marine organisms.
Only a few claims have been made so far by the some 50 coastal states who could submit them. Russia, Australia, France and Brazil are among those to have made claims, and Moscow boldly planted a rust-free Russian flag beneath the North Pole last month in waters more than four kilometres deep.
The foreign office spokeswoman said Britain had lodged one joint claim with France, Spain and Ireland for extended territorial rights in the Bay of Biscay, and hoped to agree joint submissions for other regions too.
The claims are based on extending existing territorial rights beyond current 200 mile limits.
"We are in discussions with Iceland, Ireland and Denmark over the Hatton-Rockall area," she said. "If different coastal states submit claims and there is a territorial dispute, the U.N. will simply park those claims and won't look them at all until any dispute has been resolved. So it is of benefit to all states concerned to submit joint claims."