Fingal County Council has rejected plans by the consortium seeking to build the massive Vega City holiday centre in north Dublin.
After a presentation to a special sitting of the council this evening, the consortium's chairman, Mr Owen O'Callaghan, said the group would look elsewhere in Europe to find a location.
"That's the end of the proposal for Dublin, and I'm afraid for Ireland because the location we selected is probably the best location in the country to guarantee such a proposal's viability," he said.
Councillors this evening rejected a motion to grant the developers, United Entertainment Partners (UEP), more time to submit detailed studies and answer viability concerns.
Speaking afterwards some councillors described the presentation as "sloppy".
Fingal county manager Mr Willie Soffe, told councillors the project contravened government policy and planning guidelines, and would have an adverse environmental, social and economic.
"This development does not have any real credibility because its scale needs a level of patronage which is simply unachievable on an island off the coast of Europe," he said.
"The infrastructure required could not be provided, water and drainage needs cannot be met, the transport capacity is impossible to supply."
UEP issued a short statement this evening expressing its disappointment. The consortium said it had submitted an outline pre-planning proposal a month ago and this evening sought a further six months to prepare more detailed plans.
The plan was to situate the centre on a 2,000-acre site at Lusk in north county Dublin. The €7 billion project was to include four theme parks, the world's longest monorail, 300,000 square metres of retail space, 10,000 apartments and 14 hotels. The project would have taken ten years to complete.
The promoters claimed the park would attract 37 million tourists annually, employ 40,000 people.
It claimed 18 major international entertainment firms, including a number of major Hollywood studios, were in negotiations about funding the project, although they refused to name the backers.