Four states, including Ireland and the United Kingdom, will begin a new round of negotiations tomorrow over rights to a massive area of seabed rich in oil and gas in the north Atlantic.
The latest talks, also involving Iceland and Denmark, on how the disputed Rockall area can be divided, will run over two days in Copenhagen.
The meeting follows failed discussions between the countries last month.
They hope eventually to reach a deal on territorial rights to the vast area — some 422,000 sq km or about five times the size of Ireland — and exploit its rich reserves.
Under a new United Nations (UN) treaty, states will be allowed to claim a greater share of the ocean floor if they can show an undisputed direct link with their own land mass, but they must apply before a 2009 closing date.
Minister for Foreign Affairs Dermot Ahern said that while he was hopeful tomorrow's talks would be "fruitful", further meetings may well be required before a deal is struck.
"Ultimately, it is in the interests of all four countries that we come to an agreement on the issue," he said. "Under the UN Law of the Sea all countries claiming rights have to reach an agreement, but we have until May 2009.
"The clock is ticking and it is in no one's interests to prevent agreement in the long term," he said.
Rockall is situated around 320km from the north west of Ireland, the Outer Hebrides off the west coast of Scotland and the southern coast of Iceland.
Denmark is claiming rights to the island and seabed through its dependency the Faroe Islands.
The Rockall meetings, which have been going on for five years, are part of wider moves by countries to lay claim to vast areas of the ocean in the search for new reserves of hydrocarbons and minerals. Each of the four countries is keen to safeguard its rights over the rich seabed surrounding the rock.
Ireland has already lodged a joint application, along with France, Spain and the UK, for a 60,000 sq km plot straddling the Celtic Sea and the Bay of Biscay.
"Our claim over the Continental shelf in the part of the north-east Atlantic Ocean known as the Hatton-Rockall is well founded," Mr Ahern said.
Diplomats from the four countries have met regularly since 2002 in an effort to resolve the issues arising from overlapping claims, most recently at the end of September in Reykjavik.
PA