Sinn Féin leader Mary Lou McDonald says she has no plans to withdraw her description of Taoiseach Micheál Martin as a “tosser” in the Dáil chamber last week.McDonald’s comment, after bad-tempered exchanges with the Taoiseach on Wednesday, was heard by the Dáil reporters who sit in the chamber and produce the official transcript of proceedings in the House. McDonald was questioning the Taoiseach about the total cost of the Dublin MetroLink project. When the Taoiseach said that the Minister for Transport was “not in a position to put a definitive price tag on it right now”, McDonald interjected: “That is my point.”The Taoiseach continued that the “focus is on getting the metro built. Again, I presume that is something the Deputy supports.”At which point McDonald remarked: “Jesus, he really is a tosser.”The remark is not audible on the video of the sitting, but was picked up by reporters and forms part of the official record.Asked if she would withdraw her comments, a spokesman for McDonald said she would not. Nor is the Taoiseach expected to raise the issue with the Ceann Comhairle when the Dáil meets on Tuesday.McDonald’s insult is part of a record of fiery exchanges between the Taoiseach and the Sinn Féin leader inside the Dáil and outside. Sinn Féin and Government on completely different timetables for Irish unity Listen | 54:50As the leader of the main Opposition party, McDonald has primacy in the Dáil in questioning the Taoiseach but their exchanges are often sour and personalised. Martin was also subjected to fierce criticism by Sinn Féin TDs last week on the party’s united Ireland position, with many speakers in the Dáil debate seeming to hold Martin personally responsible for the absence of a unity referendum. The Ceann Comhairle maintains a list of expressions and insults that may not be used in the chamber, though “tosser” is not yet among them.Oireachtas records show the word has been used 25 times, in various senses, in Dáil debates over the years.