Minister for Justice Charlie Flanagan has said Nóirín O Sullivan's decision to retire as garda commissioner was entirely her own, and said that he is not ruling out the possibility of someone from within the force replacing her.

Speaking on RTÉ’s News at One, Mr Flanagan said Ms O’Sullivan’s departure was her choice and "made in her own time on a unilateral basis," adding that "of course he accepted" her decision.

He said he is pleased the appointment of a new commissioner is under way and how the process is being carried out.

"Both the Policing Authority and Public Appointments Service will conduct this process in a way that is inclusive that anyone with an appropriate level of expertise across a range of areas will be eligible for appointment and I expect it will be open for all."

The minister said he wanted to stress that there will be no delay in the ongoing process of garda reform, maintaining there will be "no pause in that process."

Mr Flanagan is in Brussels today, where he attended the European Union Justice and Home Affairs Council meeting, where tackling terrorism and border controls were on the agenda.

He said they spent much of their time discussing how best "to protect our people by the sharing of information among police forces", adding that while a terrorist attack is unlikely in Ireland, it must be ensured the country is prepared to respond in the event of an emergency.