Taoiseach Enda Kenny has rejected accusations he is a dictatorial leader with an uno duce una voce style synonymous with Benito Mussolini.
Fianna Fail leader Micheal Martin launched the scathing attack and accused Mr Kenny of forcing through the referendum on the abolition of the Seanad without debate.
"It ill behoves any member of the Fianna Fail party to accuse me of being a dictator," Mr Kenny said.
"Far from that, I probably am the most open person who has handled this office and had the privilege of sitting in this office.
"My politics are about the people and the country. From that point of view, I object to the political assertion made by the Deputy Martin."
As well as the link to the fascist Mussolini, the term was famously used in a call for Fianna Fail to unite in the 1980s under Charlie Haughey's rule.
Closing the Fine Gael parliamentary party think-in in Killenard, Co Laois, the Taoiseach insisted a public vote on whether the upper house should be scrapped was fair and democratic.
Mr Martin, at his own party's meeting in Waterford, had said: "Because of this, how would I put it, 'uno duce una voce', approach of Enda Kenny and his people and the dictatorial approach, people are afraid to vote against it."
Meanwhile, amid speculation that the Taoiseach and Tanaiste Eamon Gilmore were on different wavelengths about plans for a Cabinet reshuffle between now and the 2016 general election, Mr Kenny insisted the pair have a "close relationship".
The Taoiseach has suggested he is planning to move ministers, but not before the end of the year.
At the Labour Party meeting in Enfield, Co Meath, Mr Gilmore said the issue had not been addressed.
"We haven't discussed it and it's something for another day," Mr Gilmore said.
"It's quite normal in the life of a five-year government that there are changes but it's not something that we have addressed yet.
"It's something we may address at some point in the future but we haven't discussed it and it's not something for today or the immediate term."
The Taoiseach confirmed the pair would discuss the reshuffle.
"There will be no reshuffle this year. The reshuffle of the Cabinet will take place in the back half of the lifetime of this Government," Mr Kenny said.
Reacting to news they could be in danger of potentially losing their jobs, ministers said they were unsurprised by the planned changes for the Cabinet.
Mr Kenny's Fine Gael deputy leader, Health Minister James Reilly, welcomed the news.
"I think any good Taoiseach will want to keep his team on its toes at all times," Dr Reilly said.
"I think he has proven himself to be an excellent Taoiseach. This Government has performed more in terms of reform than any Government in a long, long time.
"And I believe by the time our term is up, we will be seen to have delivered the greatest amount of reforms since the foundation of this state."
Environment Minister Phil Hogan said it is a matter for the Taoiseach to make appointments and that had indicated there would be a review of "personnel" around the half-way point of the Government's term.
Meanwhile, Jobs Minister Richard Bruton said it was Mr Kenny's "prerogative" to reshuffle Cabinet.
"Until I hear news to the contrary, my task will be to try to get the economy and the jobs situation going," he added.
Elsewhere, the health minister revealed his department is likely to need extra funds in the forthcoming budget to claw back this year's overspending.
The Taoiseach said he was not overly concerned by the overrun in the Department of Health, which is currently around 60 million euro, compared with 250 million euro in 2012.
He said Dr Reilly had assured him the department was working hard with the Health Service Executive and other agencies to ensure the money would be recovered.
Dr Reilly suggested the overspend was unexpected given the nature of his department.
"If we're a couple of euro over in the overall scheme of things, I don't want us to be over budget, but I accept fully that in health, we have a serious demographic issue to deal with," Dr Reilly said.
"What I mean by that is we have an ageing population. Older people tend to have more than one illness, tend to be admitted for longer and tend to need more care.
"We don't gain from the tremendous improvement in our economy immediately the way other departments do, because when people get a job we leave them with their medical cards for a couple of years as a safety net to encourage them back to work."