Sinn Féin TD Jonathan O’Brien has accused Micheál Martin of "cynical opportunism" in opposing the Property Tax which his party promised to introduce in its four-year plan for Government.
It is expected the tax, which will be based on 0.2% of the value of the home, will come into force next July.
Mr Martin had said that the mooted tax "is the wrong tax at the wrong time".
The Sinn Féin TD said: "When Micheál Martin says it’s the wrong time to introduce this tax what he really means is that his party is not in government at this time and therefore he will oppose his own proposal for the sake of opposition."
Deputy O’Brien has urged the Government not to introduce the tax in next week’s Budget and instead give consideration to Sinn Féin’s wealth tax proposal.
Mr O’Brien said: "This is a deeply flawed proposal that will put further unnecessary hardship on ordinary families who are already bearing the brunt of the crisis.
"Unlike other parties who oppose for the sake of opposition, Sinn Féin has put forward an alternative to the government’s property tax and this week our Finance Spokesperson Pearse Doherty published legislation for a wealth tax which would ensure that those who can afford to pay more are made to do so.
He said that the Government should protect ordinary families in the economic crisis.
Mr O’Brien said: "Micheál Martin’s opposition to the property tax is nothing more than cynical opportunism. This is the tax that Fianna Fáil promised to introduce in its four-year plan for government.
"He has no alternative proposal and, make no mistake about it, if he were in government now he would be introducing this tax. He and his party have no credibility on this issue."