Dublin - With a traditional eve-of-vote news blackout in operation in Ireland Wednesday, the country's three leading political parties, who have pushed hard for a yes vote, were holding their breath ahead of the referendum to ratify the EU Lisbon Treaty Thursday.

As polls show the result of Thursday's vote is balanced on a knife-edge, Prime Minister Brian Cowen told Irish national broadcaster broadcaster RTE Tuesday that if there was a no vote, Ireland could not wait another eight years for reform of the EU in order to compete with emerging economies such as China and India.

He added that Europe would go back to an uncertain situation if the Lisbon Treaty was defeated.

Cowen emphasized that all of Ireland's concerns had been catered for in the treaty, RTE reported.

He said it was his deeply held belief that the Lisbon Treaty was crucial to Ireland's future prospects. He was convinced people would see through the negative arguments and expressed confidence that by close of polls the yes side would have prevailed.

Opposition Fine Gael leader Enda Kenny described Thursday as "a moment of truth" for Ireland.

Labour's Eamon Gilmore said a no vote would result in confusion and uncertainty with people worried about their jobs.

Figures released Tuesday showed Irish unemployment above 200,000 for the first time since 1999, the equivalent of 5.4 per cent of the workforce.

This "was not the time for Ireland to raise doubts about our relationship with Europe," he said.

Together the three parties hold 149 seats in the 166-member Dail (lower house). Only one party with parliamentary representation - nationalist Sinn Fein with four seats - has opposed the treaty.

Sinn Fein President Gerry Adams says he wants the government to renegotiate the Lisbon Treaty to include opt-outs or vetoes on issues such as neutrality, public services and workers' rights.

A no vote would torpedo the ambitious Lisbon Treaty, which is designed to reform the 27-nation bloc and make it more efficient and effective in dealing with the challenges posed by globalization.

In 2001, Irish voters rejected the Nice Treaty, another reform project, but ratified it in a second vote 16 months later after a declaration was inserted clarifying Irish neutrality.

This time around it is fears about job security, farming, taxes and religion that have dominated the debate in a country that has been one of the main beneficiaries of EU largesse.

The mood has also been affected by a sharp fall in growth that has raised fears the "Celtic Tiger" is losing its bite, leaving people worried about their financial future.

Sinn Fein has claimed the treaty would open the door to tax harmonization, forcing Ireland to scrap the low corporate taxes that have attracted many foreign companies to the country.

European Commission President Jose Manuel Barroso has taken pains to point out that approval of the treaty would still leave Ireland with a veto on tax issues.

But no campaigners accused the EU chief of putting a gun to Irish heads when he stated in Brussels recently that Europe "will pay a price" if voters reject the treaty.

Latest opinion polls show the outcome of the referendum hangs in the balance.

There has been a surge in support for the no campaign to 35-39 per cent, while those backing yes are down to between 30-42 per cent, leaving around one-third of the 3.1-million electorate undecided. (dpa)