The site of a massive ancient pagan temple unearthed at one of Europe’s most archaeologically significant sites will be buried under a controversial motorway, campaigners warned tonight.

Fears were growing that the Government is to plough ahead with the contentious M3 route despite the discovery that has excited heritage campaigners.

The Government insists it has not decided the future of the major find near the historic Hill of Tara in Co Meath, uncovered just 24 hours after Transport Minister Martin Cullen turned the first sod on the project.

While work has been suspended to allow further examination, the Government is today fending off claims by campaigners that this is merely a stay of execution for the site.

Environment Minister Dick Roche is consulting National Museum director Pat Wallace on the best way to proceed.

But Vincent Salafia, an environmentalist and long standing Save-Tara campaigner, claimed the Government was committed to developing the motorway regardless of the impact.

He alleged Mr Roche had already taken the decision to demolish the ancient find - though the minister denied the allegation.

Mr Salafia claimed documentation has already been drafted on the Government’s plans for the site.

“In these directions, Minister Roche directs that the national monument be preserved ’by record’,” he said.

“In other words, excavations will resume in a matter of days, and the massive enclosure will then be demolished.”

The Irish National Monuments Act allows for the partial or complete destruction of national monuments, or finds of significant importance, by the Government if it is deemed to be in the public interest.

The National Museum director is consulted but has no veto over any Government decision.

A spokesman for the Minister insisted a decision had not been made, stating consultations between Mr Roche and the National Museum were ongoing.

“Whatever these people (campaigners) are saying is just purely speculative,” he said.

The newly-discovered large circular enclosure, said to be a Henge structure, or ancient pagan temple, is thought to be around the size of three football fields and was used for Iron Age or Bronze Age rituals.

It did not appear on any of the extensive tests carried out in advance of the motorway project getting the go-ahead.

The Hill of Tara is one of the most important links to ancient Ireland and one of the most significant archaeological landscapes in Europe.

The site was the seat of Ireland’s pre-Christian High Kings and marks the spot where Irish myth and Irish history intertwine.

With its passage tomb, earthworks and prehistoric burial mounds, it is viewed as the mythical and ceremonial capital of Ireland, dating back 5,000 years.

Historians have long been baffled by its mysteries, with only partial, unconnected ruins found to date, leading experts to believe there may be many more undiscovered treasures.

The controversial proposed M3 motorway is designed to ease the traffic chaos of towns along the Meath corridor.

Residents in the Dublin dormitory county are all too aware of the great need to solve the congestion difficulties, with massive tailbacks during peak times.

Campaigners fought unsuccessfully in the High Court to have the route of the motorway diverted to avoid the Hill of Tara site.

Conor Newman, Professor of Archaeology at NUI Galway, said he was pessimistic Government would save the site.

“The campaign to preserve this site has become a legal battle when in fact it should be an ethical one, whether we value our heritage or not,” he said.