Taoiseach Brian Cowen has again appealed for a Yes vote on Thursday saying it was crucial to this country's future prospects. He flatly rejected the idea that it would be possible to renegotiate a better deal if there was a No vote.
He said that Fianna Fáil had carried a positive message to the people for the past four weeks but had been faced with "a dishonest campaign" from those advocating a No vote.
"Five times previously, Ireland has voted Yes to Europe and on each occasion it has resulted in more jobs, more investment and more trade," Mr Cowen told the final Fianna Fáil press conference of the campaign.
He said that voting Yes to Lisbon would underline Ireland's place at the heart of Europe and demonstrate to investors, both national and international, that investing in Ireland remains a sound proposition.
"As Taoiseach, it is my deeply held belief that the ratification of the Lisbon Treaty is crucial to this country's future prospects.
"This is a view I share with the leadership of all the major political parties, all of the leading organisations representing business and industry, large and small, the Irish Congress of Trade Unions and all of the agriculture and farming bodies.
"All of these groups have put the interests of Ireland first and come together to support the Lisbon Treaty's passage. If we want to move forward as an economy, as a society and as a nation we should vote Yes on Thursday," he said.
Mr Cowen said that during the past four weeks Fianna Fáil had carried the debate on the Lisbon Treaty into every community in the country and its message had been a positive one about Ireland and the European Union.
"I am very proud of the work of my party which has continued our tradition of a deep commitment to the European ideal. This work will continue right up to 10 o'clock on Thursday evening when the polls close.
"Thursday the 12th of June 2008, will be an important date in Irish politics. Whatever the result it will mark a major statement about who we are as a people and the future we want to build," said the Taoiseach.
He said the Irish people would have to decide if they wanted to move forward as positive members of the European Union, helping it to reform and working with other states to meet modern challenges, or if they wanted to take a new and more uncertain route.
"To those who say 'go back and start again' I have a very clear response: this is an excellent Treaty. It was shaped by Ireland more than any previous European document in 35 years of our participation in the great European project.
"We don't want Ireland's influence damaged in pursuit of an unclear, defensive and negative agenda, which will clearly occur if a No vote is successful on Thursday," said Mr Cowen.
He said nobody wanted to wait another eight years before the EU could start work on the serious issues for Ireland and for Europe including climate change and cross-border crime.
"Future generations will not thank us if we are the ones who bring to a halt a Union which has been the greatest force for peace and prosperity in our history and the history of Europe.
"Our future success flows from re-affirming our commitment to the European Union. In an ever more competitive global environment, it is imperative we don't give the impression that we are turning our back on Europe," he said.