Dónall Ó Cualáin, the Acting Garda Commissioner, has revealed he will not put his name forward to replace Nóirín O'Sullivan.

Mr Ó Cualáin told a private meeting of garda management that he will remain in situ until Ms O'Sullivan's successor is appointed, Independent.ie can reveal.

Following queries from Independent.ie, the Acting Commissioner confirmed his decision.

“I am honoured to have been appointed Acting Commissioner. My focus as Acting Commissioner is to ensure that An Garda Síochána continues to protect and support communities, while progressing the significant changes to the organisation under the Modernisation and Renewal Programme," he said.

Mr Ó Cualáin spent several years serving as a sergeant on the Aran Islands.

Since leaving the Aran Islands for the mainland, Mr Ó Cualáin is seen as someone who has risen through the force without trace.

Colleagues point out that unlike Ms O’Sullivan, many of his roles have been focused on strategy and planning - rather than front line policing.

“Donall would be unusual insofar as he has not spent a whole lot of time in the policing frontline. Nóirín at least was a street cop and was proud of that background. In fact she was the last garda to arrest crime boss Christy Kinahan back when she was in the Drugs Squad,” said one senior officer. “Donall is a very different fish altogether coming through the office route.”

In the mid-nineties, Mr ÓCualáin spent a short stint in the Organisational Development Unit in Garda Headquarters.

Since renamed the Policing and Planning Unit, officers based here spend their time researching other law enforcement agencies in order to improve the effectiveness of An Garda Síochána.

Only those with postgraduate qualifications take up a role in this unit.

Mr Ó Cualáin fulfilled the criteria required to land a job in this office with his qualifications from NUI Galway and Harvard.

Following his promotion to the post of Chief Superintendent in 2005, the officer served for a short period in the divisions of Mayo and Sligo before taking charge of the Galway division.

In July 2012, Mr Ó Cualáin got his first major break when he was appointed assistant commissioner with responsibility for the southern and then the western regions.

Just five months after Martin Callinan’s resignation, his replacement Ms O’Sullivan appointed Mr Ó Cualáin as deputy commissioner with responsibility for governance and strategy.

Sources say he developed a close relationship with Ms O’Sullivan and was part of her inner circle.

He regularly sat alongside Ms O’Sullivan as she faced grillings from TDs at various Oireachtas committees.

He was also given the task of examining the practice of 999 calls being recorded in garda stations - which was the subject of the Fennelly Commission.

Mr Ó Cualáin once again returned to his roots in 2015 when he was appointed head of the western division.

Given his predominantly office-focused environment, sources say there will now be a big focus on his battle against crime.

“He has concentrated on the office environment and in academic qualifications and outside of the Garda Headquarters he would not be as familiar with the crime scene in Dublin, organised crime or the terror situation. In terms of background he is the first uniformed branch garda to fill the role since Larry Wren,” an officer said.

“This probably will mean the detectives or investigators will be looking for him to show his mettle in the battle on crime. That is something that will be closely watched by the specialist units who carry a lot of sway in the modern police service,” the source observedÓ