Simon Coveney is to appear before an Oireachtas Committee on Tuesday to answer further questions over the appointment of Katherine Zappone as special envoy.
Mr Coveney had asked to appear before the Foreign Affairs and Defence committee as soon as possible to provide clarifications requested by opposition parties.
Earlier, he revealed that gardaí investigated after his mobile phone was hacked in 2020.
The Minister for Foreign Affairs, in a letter sent on Thursday to the Chair of the Foreign Affairs and Defence Committee Charlie Flanagan, said that his phone was “compromised” last year.
He says that his hacked phone was used to contact other European foreign ministers.
In the letter, Mr Coveney tells the committee: “Some of my foreign minister colleagues across Europe were contacted using my phone’s identity as a front during that hacking incident.
“I believe the matter was dealt with swiftly and thoroughly by my department and the Gardai from whom I take ongoing advice.”
“As a result of this incident and others, I work on the basis that very few telecommunications are completely secure,” he said.
Earlier this week, the Garda Press Office declined to say whether gardaí had investigated a hack on Mr Coveney’s phone.
In the letter, Mr Coveney denies he was trying to keep messages secret and offers to come before the committee to answer questions.
He said: “It was me who told the committee that the Tánaiste had raised the upcoming Zappone appointment with me by text and this has been shown to be completely consistent with what the Tánaiste’s text messages show.
“What I did not know in the committee was why the Tánaiste had initiated this text conversation.”
Mr Coveney says that he was “completely honest” with members of the committee about his interactions with Mr Varadkar.
“I accept that the Tánaiste’s text to me shows he was aware of the special envoy position in his opening question to me and that the process of appointment was near completion.”
Mr Coveney tells the committee that it is “plain wrong” to suggest he was trying to keep texts secret and rejects the idea that he misled the committee.
Speaking on Thursday evening, Sinn Féin leader Mary Lou McDonald said that Mr Coveney had been “misleading” during his committee appearance.
“It’s very clear that he was less than forthcoming and in fact he was misleading in the testimony that he gave to the committee, so he needs to correct to that. I think we need now a full and honest account of how all of this happened.”
Speaking in Newry earlier on Thursday, Mr Varadkar said the appointment of Ms Zappone as a UN special envoy on freedom of expression “wasn’t handled in the right way”.
He said: “I don’t think it’s being overshadowed. It’s certainly a shadow, but I don’t think it’s overshadowing what is a really important day for the Government, for the country.
On Ms Zappone’s appointment, Mr Varadkar said: “It wasn’t handled in the right way. Unlike other special envoys, it was politically sensitive because she was a former Cabinet member.
“There was a responsibility on Simon or me, or both of us, to inform the Taoiseach and Minister (Eamon) Ryan in advance. We didn’t do that. That’s essentially what happened, and we need to ensure that doesn’t happen again.”
The Tánaiste denied that it reflected badly on the Minister for Foreign Affairs that while he himself has released text messages related to the appointment, Mr Coveney had deleted his, saying he had done so because his phone was hacked.
Mr Varadkar said: “The difficulty is I suppose, Simon, when he was making his account to the committee, had deleted the texts.
“I still had them, so I was able to jog my memory and remember what had happened or not.”
On Wednesday, Mr Varadkar released a series of text messages exchanged between himself, Mr Coveney and Ms Zappone.
The texts reveal conversations about Ms Zappone’s controversial appointment as a UN special envoy, a role which she later relinquished.
The exchange shows Mr Varadkar was asked by Ms Zappone about her appointment 11 days before Cabinet met to approve her for the role.
It also emerged that Mr Varadkar and Ms Zappone discussed the role during an event at the Merrion Hotel event in July.
On Thursday Mr Varadkar said the first he had heard of the Zappone appointment was in a text from Mr Coveney on July 19th.
