If land in Antarctica was purchased in blood then Britain would probably have the strongest claim. Many sons of this small island lay dead in this frozen continent, or died there, only later to be repatriated and buried in the soil of their homeland.
When you look at the history or exploration, a lot of the areas on the maps were drawn by British explorers. They established a claim on the Falkland Islands before anyone else knew they were there and established an outpost to aid and assist ships moving through the Cape Horn. From there they established Whaling Stations in the South Georgia Islands.
Britain has been a part of Antarctic exploration and exploitation since Queen Elizabeth the First.
They have also been one of the first to realise the potential to destroy this precious area. Britain was one of the first to abandon whaling, were one of the first to sign the treaty for the peaceful exploration of Antarctica and have been foremost with retaining a presence in Antarctica, with the assistance of the Australians.
Britain's claim comes from not only discovering and charting much of Antarctica, but also in exploring it. Scott, Oates and others died trying to reach the South Pole and return, Shackleton and his men endured a nightmare there, and with their former colony Australia, they have established numerous scientific outposts devoted to understanding and unlocking this frozen continent.
Britain has more than enough right to step up and ask for a piece, they have given blood for this continent, probably more blood than any other.
Admittedly, Britain's early interest was primarily economic, and were looking at resources to exploit, and let's face it, every country that has staked a claim to Antarctica is guilty of that, but over the years as economies have changed the needs and people's perceptions have altered, Britain moved forward to preserve Antarctica as a pristine wilderness.
One could say that with so many British lives lost in Antarctica and so much of the Early exploration of the continent done by them, what right does America have to claim so much of Antarctica, it is hardly next door to it, or borders it.
Britain's claim is through it's former colonies, Australia and New Zealand, both of which are jump off points for many of the scientific stations there. Both Australia and New Zealand have flights directly to Antarctica.
Both Australia and New Zealand admit that Britain was there mother country and that most of their programs and interest in Antarctica, is a legacy of their time in the British Empire. So, if Britain wants to grab a piece of a continent they helped pioneer, they should be allowed to, they have lost so many sons to that great white wilderness, can any other country honestly else say that.