The policing authority is to begin looking for a new Garda Commissioner today.

Noirin O'Sullivan announced her shock retirement yesterday - saying her job had become an unending cycle of public hearings and responding to inaccurate commentary.

The first ever female lead had been facing calls to step down after a number of controversies in the force, including the breath test and whistlelower scandals.

In a statement, Mrs O'Sullivan suggested that "responding to an unending cycle of requests, questions, instructions and public hearings" had gotten in the way of her efforts to reform the force.

Taoiseach Leo Varadkar echoed Mrs O'Sullivan's statement, saying the decision was made "in the best interests of An Garda Siochana".

Opposition parties, meanwhile, have welcomed the news.

Fianna Fáil said it "paves the way for a new chapter for An Garda Síochána", while Sinn Féin Deputy Leader Mary Lou McDonald suggested it had been clear "for some time now that Commissioner O’Sullivan’s position was untenable".

Sinn Féin Deputy Leader Mary Lou McDonald says it was clear that the Commissioner had to go.