Fianna Fáil TD Barry Cowen has been sacked as Agriculture Minister by Taoiseach Micheál Martin.
Mr Martin has told the Dáil Mr Cowen is not willing to address publicly further concerns in relation to his drink-driving claim, which has raised legitimate doubts.
"The President on my advice this evening terminated the appointment of Deputy Barry Cowen as a member of the Government.
"Pursuant to Section 41 of the Ministers and Secretaries Amendment Act 1946, I've assigned the Department of Agriculture Food and the Marine to myself.
"And I will propose the appointment of a new member of the Government tomorrow if the House can facilitate it.
"This is a very sad day for Barry, his family and for me", Mr Martin said.
He added: "Over the course of the last 10 days he has the subject of significant criticism and condemnation for a road traffic offence that took place in 2016.
"He has been completely clear and unambiguous regarding his drink-driving offence - he gave a personal statement to this House on July 7th, in which he talked about the stupidity of his actions, he accepted what he did was absolutely wrong and he apologised to all members.
"I accepted that his remorse was genuine and I accepted his apology.
"When he was first confronted with the allegations, Minister Cowen was immediately clear and emphatic about this drink-driving offence and understood the need to acknowledge this.
"However he was equally clear and emphatic that one detail of the allegation he was being presented with was completely untrue - namely that he sought to evade Gardaí at the time.
"We've had extensive discussions on this point last evening and again this morning, when he shared with me for the first time the actual Garda record under dispute.
"Following these discussions and having seen the Garda report this morning, it was my view that it raised additional issues requiring further explanation and clarification."
"He has decided that he's not prepared to address this allegation publicly, and will not make any further statement or answer any questions on this issue in this House.
"This decision has created a situation where legitimate doubts and additional questions are being raised and Government colleagues are expected to address these.
"This is simply untenable".
He said Minister Cowen had an obligation to come before the House, and that this issue is "damaging to the ongoing work of Government".
In a response on Twitter, Mr Cowen has hit out at Mr Martin's decision - claiming it has undermined his entitlement to fair process in the investigation about the leaking of his file.
He said he was surprised and disappointed with the decision to remove him as minister.
He also queried why the Taoiseach backed him in the Dáil earlier on Tuesday, but changed his mind.
(1) The Taoiseach informed me this evening by phone that he was removing me from office as Minister for Agriculture.
I am both surprised and disappointed with this decision.
— Barry Cowen (@CowenBarry) July 14, 2020
Last week, Mr Cowen apologised in the Dáil for the 2016 incident which he described as a "stupid, stupid mistake."
He also said it was "not uncommon" for people of all ages to drive with either a provisional licence or learners' permit at the time.
He told deputies he wanted to "officially put on the record" the facts of the incident.
He confirmed he had consumed two drinks before attending the All Ireland Football Final in Dublin in 2016, before eating a light meal after the match.
While driving home to Offaly, he was stopped and breathalysed.
After being found to be over the legal alcohol limit, he was given a €200 fine and a three-month driving ban.
He held a learner drivers' permit at the time as his previous provisional licence had lapsed.
He said: "Before the recent and proper reforms of the system, it was not uncommon for people of all ages and level of experiences to drive with either a provisional or learners' permit. However, this was bad practice - and I clearly should have regularised my position much sooner."
After reports of previous parking and speeding fines, Minister Cowen said he examined his records and found the only additional, unreported event he was able to identify was "a failure to display a parking disc while parked in Tullamore 14 years ago".
An investigation was subsequently launched by GSOC into the possible leaking of information about the drink-driving ban.
In a statement on Sunday Mr Cowen said: "The Sunday Times has today published an article referring to an incorrect Garda record dealing with the incident which occurred on 18th September 2016 despite the fact that my solicitors wrote to the newspaper in advance of publication.
"I did not evade, or attempt to evade, a Garda. Such an act would constitute a serious criminal offence and I was not charged with such an offence.
"On being informed of its existence I sought a copy of this incorrect record and am taking steps under the Data Protection Act to have it corrected.
"This incorrect Garda record can only have come into the possession of the newspaper through a criminal act.
"It is a criminal offence for a member of An Garda Síochána to disclose any information obtained in the course of his or her duties.
"I am informed that An Garda Síochána has commenced a criminal investigation into the source of this leak."
Following this, GSOC said: "As Minister Cowen's statement constitutes a complaint against a member or members of An Garda Síochána the Commissioner will be referring the matter to GSOC for its consideration."