About 60 people protested outside the Shell oil company's offices in Dublin yesterday, in opposition to the Corrib Gas pipeline.
Members of the Shell to Sea Campaign chained bicycles across the entrance to the offices on Adelaide Road, in what they said was a symbolic precursor of planned blockades of Shell installations in Mayo.
The protests were mirrored by pickets at Shell offices in the Netherlands and Britain and Shell filling stations in the west of Ireland.
Co-ordinator of yesterday's protest Tadhg McGrath said the campaign was frustrated "by Shell's lack of a plan B or any alternative" and believed the oil company would press ahead with construction of the Corrib Gas pipeline in March.
But he said the campaign was prepared to take "direct action" to prevent the construction work going ahead. "We have heard that Shell has block-booked hotels and guesthouses in Mayo for an Italian construction crew. But at the end of this month the Shell to Sea camp will be up and running again in Mayo and we are prepared to blockade their work."
Mr McGrath said funds had been raised internationally over the winter and members had travelled abroad, visiting protest camps and amassing equipment necessary to mount a "Greenham Common" style protest.
Yesterday's protests were part of a weekend of events which continue in Ireland, Britain, the Netherlands and Sweden today.
A highlight of today's events is likely to be a protest as Taoiseach Bertie Ahern addresses an Ógra Fianna Fáil convention in The West County Hotel, Ennis, this evening.
Meanwhile, Shell E&P Ireland has called for a "cooling" of the debate over the €900 million Corrib gas project. The company has also confirmed that former Mayo county secretary Pádraig Hughes has been engaged on a consultancy basis.
Commenting on yesterday's protest Shell E&P Ireland's managing director Andy Pyle urged the "five men from Rossport "to resume mediation talks. We are never going to solve the problems we have in Rossport if we are constantly arguing with each other. There is a mediation process in place, which the five men from Rossport have stepped out of at the moment. I call on them to resume talks so that they themselves and Shell can sit down face-to-face and start working out a solution to this problem." The company was "fully committed to addressing the genuine concerns of the local community" and believed the twin procedures of mediation and the Government safety review of the onshore pipeline could lead to a resolution of issues.
"The Corrib gas project could bring fantastic benefits to Erris and Mayo generally and is essential for Ireland's security of energy supply," Mr Pyle said.
"It's about time we took some of the heat out of this problem and started talking constructively - dialogue is the only way forward."
The five men jailed for 94 days last year over their opposition to the pipeline again called on the Minister to clarify recent comments which led to the men's decision to suspend mediated discussions with Shell.
The Minister had "unilaterally changed the format of mediation", the five said. Time, space and confidentiality were required to reach agreement, but the Minister had "removed that possibility" and had either "consciously misled us or reversed his September position".