The number of TDs boycotting the new household charge has now risen to 18.
Sinn Féin's Pearse Doherty has become the most high profile of the deputies opposing the new €100 charge, which comes into effect in January.
The campaign against the new charge was originally kicked off by nine opposition TDs yesterday, who claimed they would rather go to jail than pay the fee - which can build up to a fine of €2,500 if it remains unpaid.
The nine included Socialist Party duo Clare Daly and Joe Higgins, along with Richard Boyd Barrett and Joan Collins of People Before Profit and independents Seamus Healy, Thomas Pringle, Mick Wallace, Luke ‘Ming’ Flanagan and John Halligan
Today seven Sinn Fein TDs have joined in on the campaign and say they too will not pay this household charge. Amongst them are Finance spokesperson Pearse Doherty and housing and justice spokesperson Aengus Ó Snodaigh.
Minister for the Environment Phil Hogan said the threat to boycott the charge, was a “cynical and emotive public relations stunt”.
He added: "I think those TDs should pull back from this irresponsible activity where they are advocating, as lawmakers, that Irish people break the law. It is a very dangerous road for our democracy.”
