There has been a renewed call for Minister for Tourism, Culture, Arts, Gaeltacht, Sport and Media Catherine Martin to step down over the circumstances surrounding the resignation of RTÉ's chairperson, Siún Ní Raghallaigh.

Opposition parties piled on the pressure in advance of the Minister for Media’s appearance before an Oireachtas committee this evening.

Siún Ní Raghallaigh resigned as RTÉ chairperson after Ms Martin refused to express confidence in her during an interview on Prime Time last Thursday and expressed her disappointment that she had been misinformed about exit packages for RTÉ executives.

Ms Ní Raghallaigh resigned in the early hours of Friday morning February 23.

The Oireachtas Committee on Media will hold a special three-hour session to examine the controversy this evening, with proceedings due to start at 7pm and being broadcast on the RTÉ News channel.

The media committee is set explore the extent of the knowledge of the change of policy at the broadcaster, which saw the remuneration committee of the main board assume responsibility for signing off on severance packages.

Speaking outside Leinster House today, Labour Party leader Ivana Bacik said that there is an “existential crisis” after Ms Ní Raghallaigh’s departure.

Ms Bacik said that Martin “has to answer the question as to why she went on Prime Time last Thursday night and effectively carried out summary dismissal of the chairperson of a state board”.

However members of the government defended the Minister for Art and Culture, with Minister for Public Expenditure Pascal Donhoe saying tha the Oireachtas Media Committee is the "appropriate place" for the Minister for Media to answer questions about the circumstances around the resignation of RTÉ Chair Siún Ní Raghallaigh.

Mr Donohoe said that every party had representatives on the Media Committee and he asked whether their parties had "little faith" in them.

His message of support contrasted the several opposition parties called for Catherine Martin to answer questions in the Dáil.

Not all political parties were as emphatic in their position as Labour with Social Democrats TD Róisín Shortall, saying: “We’re not in the business of calling for heads.”

However, she did say: “It’s becoming increasingly obvious that Minister Martin made a serious blunder last Thursday in going on the Prime Time programme.

Sinn Féin leader Mary Lou MacDonald said of the situation that: “A lack of transparency and accountability has broken public trust in RTÉ and it now seems the minister is not prepared to be fully transparent and accountable,” she added. “That is not an acceptable situation.”

The leader of the opposition went on to say that: “The same minister was quite prepared to go on live television and without any prior notice sack Siún Ní Raghallaigh, but she’s not prepared to come before the chamber and answer questions,” she said.

Ms McDonald said the minister had “badly mishandled the RTÉ debacle” and had now “added to the chaos”.