Campaigners opposed to the M3 motorway running through the historic Tara Valley have started to hold a series of demonstrations in three different countiries today.
TaraWatch held protests outside Leinster House in Dublin and the Irish Embassy in London earlier.
There will be protests later in New York, Boston, Chicago and Los Angeles.
A protest march will also be held in Dublin on Saturday, July 21st at 1pm, which will go from the Garden of Remembrance to Custom House, the headquarters of the Department of the Environment.
Campaigners have said they are "inflamed" by what they describe as the Green Party's election pact with Fianna Fáil to agree to the M3 motorway project and today's announcement by Environment Minister John Gormley that the Government will not re-route the road despite Euopean criticism.
The demonstrations come as Minister for the Environment John Gormley holds talks today with European Commissioner for the Environment Stavros Dimas in Brussels.
Campaigners claim international support has grown rapidly since the World Monuments Fund designated Tara one of the World's 100 Most Endangered sites.
Darren Delahunty, one of the organisers of the London protest, said: "Irish people in the UK are outraged at the refusal of the Irish authorities to try and proceed with the road, even when the public are so against it."
A "Love Tara" march will be held on Saturday, July 21st, in Dublin.