Ascension Island is already part of the British overseas territory of St Helena. Britain made the claim to the United Nations Commission for the Limits of the Continental Shelf on the ground that the island's landmass reaches much further underwater and wants to extend its rights around the island, the British Broadcasting Corporation (BBC) reported.
States have rights over their resources including oil or gas reserves up to 200 nautical miles from the shoreline. Since there are no other states involved, the success of the case is likely to rest on the degree to which Britain's claim is valued scientifically, said the report.
Fight for control of the world's sea-bed has intensified in recent years as new technology makes any reserves of oil and gas much more accessible. However, as fewer than half of the world's maritime boundaries have been agreed, experts believe there might be more conflicts where more than one country lays claim to overlapping areas.
Britain submitted a joint claim with France, Spain and the Irish Republic in 2006 for the continental shelf in part of the Bay of Biscay. It is reportedly also considering a similar claim around the Falkland Islands, where it is thought to have oil and gas reserves.
Britain is also in discussions with Iceland, Ireland and Denmark - on behalf of the Faroe Islands - about a joint claim in the Hattan-Rockall area of the North East Atlantic, off the west coast of Scotland, said the report.
