Taoiseach Bertie Ahern accused Labour leader Éamon Gilmore of casting a slur on civil servants during heated exchanges.
Mr Gilmore claimed that the Government's communications unit "was effectively a political operation and that it is in place to provide political spying and reporting on the press and critics of the Government". It was costing the taxpayer €400,000 annually, he added.
Mr Ahern said that the unit was not like party press office "that misrepresent statements" in the House every day. "That is not its function."
Mr Gilmore claimed: "The unit tots up the number of times Professor [John] Crown or any other critic of the Government appears on radio and sends the information to the departments so that the political apparatchiks who do not want to see the critics anymore can say that to the news editors".
Mr Ahern said: "I object to everything Deputy Gilmore said. He is entirely wrong and has made a slur on civil servants, namely, that they are doing a job they are not doing. This is a reprehensible attack on civil servants by the leader of the Labour Party. He is entirely wrong."
Mr Gilmore replied: "It is not an attack on civil servants. The Taoiseach is abusing the Civil Service."
Mr Ahern claimed that the Labour leader was "challenging the ethics of the Civil Service and is entirely wrong". He added that Mr Gilmore should withdraw what he had said, given that it was not becoming of him. "I reject it entirely."
Mr Gilmore said: "I cast no slur on the Civil Service. I never have and I have always respected the independence of the Civil Service. We are very well served by an independent Civil Service. However, the Taoiseach and the Government are abusing the Civil Service."
Earlier, Fine Gael leader Enda Kenny said that his party colleague, Fergus O'Dowd, had submitted a freedom of information request about the output of the communications unit in mid-June to see if it flagged a media report June 13th, which stated that Aer Lingus was to introduce new routes from Belfast.
That announcement, as everybody would be aware, he said, led to the cessation of Heathrow flights from Shannon and the transfer of the slots to the Belfast-Heathrow route.
Mr Ahern said the unit disseminated a summary of radio and television news headlines. It did not list everything in every newspaper every day, but it would always pick up the headlines, major stories and editorial stories.