After 15 years of lobbying by Australia, the UN has found that the country's territory should be extended by 2.5 million square kilometres, an area roughly five times the size of France and about 10 times the size of New Zealand or the United Kingdom.

"Australia has just been dramatically increased in size," Ferguson told reporters in Canberra, according to AAP.

"We have fully explored through the United Nations our entitlements to actually extend our continental shelf."

Ferguson said no one could put a figure on the likely petroleum resources in Australia's newly acquired offshore territory, which is virtually unexplored, but he believed the potential was huge.

Certainly, extensions taking in the Wallaby and Exmouth Plateaus, the Great Australian Bight and the Lord Howe Rise encompass areas considered by Geoscience Australia to hold promise.

Australian Petroleum Production and Exploration Association chief executive Belinda Robinson says not much is known about the new areas.

"Yesterday's announcement leaves a lot of unexplored territory that may produce the next Australian oil and gas province," she said

"In terms of most of the areas that we're looking at we know very, very little [but] a number of them are adjacent to existing producing areas, the Carnarvon Basin for example and the Browse Basin in Western Australia, so we'd be hopeful that they may be prospective."

But simply having jurisdiction over the acreage was not enough for Australia, according to Robinson.

"The challenge for Australia is to persuade potential investors to risk money here rather than elsewhere," she said.

"This requires a two-pronged approach - to ensure the availability of baseline geological information [and] to ensure that the fiscal framework takes account of the high costs and high risks involved in exploring these areas."