Sinn Féin TD Jonathan O'Brien said telling another Dáil member to "shut your mouth" last night was born of "pure frustration".
The Cork Deputy revealed in the Dáil yesterday that his brother, a recovering heroin addict, is unable to find suitable accommodation.
His comments were in response to the Tánaiste in Leader's Questions, who was speaking on the issue of emergency accommodation.
The Tánaiste responded to O'Brien's surprise declaration by telling him: "Don't you dare lecture me."
A small section of the exchange can be seen at 39 minutes.
However, it was Labour TD Eric Byrne's comment, when he asked O'Brien why his family wasn't taking care of his brother, that sparked a controversial exchange.
O'Brien told Byrne: "shut your mouth! Shut your mouth!" before leaving the chamber.
In an interview with the Irish Mirror in the wake of the incident, he told the paper Deputy Byrne made "cruel" remarks, and "He is a d***head."
"To be honest, it's not something I planned on doing - it was born out of pure frustration ... I probably spoke before I engaged with the brain," he told Newstalk Breakfast.
"I basically lost the rag."
He said it was vitally important that people coming out of rehabilitation find accommodation that is removed from a drug-taking environment.
"Some of the TDs in there [the Dáil], they're just not aware of what's happening on the ground."
In the wake of the incident last night, other deputies suggested that O'Brien should withdraw his remark, with Fine Gael's Derek Keating saying "that is completely out of order."
Eric Byrne, the subject of O'Brien's remark, replied: "What would one expect from Sinn Féin?"
O'Brien's party colleague, Pádraig MacLochlainn, intervened, saying "In the circumstances, members should have a bit of common decency and cop themselves on."
— Transcript provided by KildareStreet.com.