A commitment that there will be no major development along the route of the M3 near Tara was given by the Minister for the Environment John Gormley at the weekend.
Launching National Heritage Week in Farmleigh, Dublin, the Minister said this was a prime example of the clash between heritage and development.
He said as Minister he could not comment on the decision of An Bord Pleanála.
However, the Heritage Council wanted to designate such zones as Tara as landscape conservation areas to prevent major development on them.
"The decision on the M3 was taken in 2003. I am the Minister in place now, and I have to take decisions now on how to protect our heritage.
"I have taken the advice of the Heritage Council. They want Tara to be designated as a landscape conservation area, and I am committed to doing that.
"That is the only way and the best way to ensure that we do not attract unnecessary development along the M3," he said.
Officially launching National Heritage Week, Mr Gormley said for the first time this year every county was participating in heritage week, and with close to 1,000 unique events taking place, there was something to appeal to all tastes.
These include late-night walks to study bats, storytelling on Cape Clear island, a medieval magic show in a castle, and learning more about the nation's heritage through guided walks and lectures taking place across the country.
A new initiative in this, the 16th year of the heritage week, was the sponsorship by the Heritage Council of events in Derry and Carrickfergus, and Mr Gormley said he looked forward to further linkages with our Northern counterparts.
He said recent research carried out by the council highlighted the public's support for a more proactive approach to protecting our heritage. National awareness of the event grew considerably last year, he said, with over 60 per cent of the Irish public being aware of the week's events.
He said Fáilte Ireland research showed that 82 per cent of tourists rated scenery as an important reason for visiting Ireland, and scenic landscapes, coastlines, towns and village were the core product of that industry.
"We must meet the challenge of protecting their distinctiveness and character for ourselves and for others if we are to ensure that our tourism industry continues to grow."
He said no generation in Ireland's history had a greater impact on the country's landscape but our aspiration now should be not how high we could build, but how much we could sustain.
Michael Starrett, chief executive of the Heritage Council, said the growing involvement from the community was unsurpassed in Europe, and there were local heritage events taking place in every part of the country.