Fianna Fáil leader Micheál Martin has said the position of Minister for Justice Alan Shatter is now untenable in the light of the continuing controversy surrounding Garda whistleblowers and how they have been treated by the force's management and the Government.

Mr Martin said Mr Shatter had made a "very serious mis-statement in the Dáil record" about whistleblower Garda sergeant Maurice McCabe which he had refused to withdraw.

“My view that for quite some time is that Minister has undermined the whistleblowers...

“Events have overtaken him and reports have overtaken him. He cannot hide behind that anymore,” he said.

Mr Martin was speaking to reporters at his party's ardfheis in Killarney. Over 2,500 delegates are expected to attend for the Fianna Fáil leaders's speech at 8.30pm.

Earlier the party's justice spokesman Niall Collins had said Mr Shatter was "not up to the job and it was time for him to go".

Mr Martin also asserted Mr Shatter’s position was untenable.

“It’s a very serious smatter when you make false allegations that cannot be stood up and he continues stubbornly to maintain that dail record is correct when we all know it isn’t.”

Mr Martin said what he portrayed as the crisis within Government on this matter was getting more serious.

He honed in on the fact that Minister for Education Ruairi Quinn had issued a public statement criticising Garda Commissioner Martin Callinan's "disgusting" comments several hours after Taoiseach Enda Kenny had said he would prefer such discussions to happen within the Cabinet.

Presenting Mr Quinn's comments as illustrative of a Cabinet split, he said the Labour Minister for Education had ignored the Taoiseach's advice given earlier that day.

“The Labour Party is not in the mood to be shut down by the Taoiseach or indeed his own Ministers.

"Other Ministers including Leo Varadkar, Simon Coveney, the Tánaiste Eamon Gilmore, Joan Burton and now Ruairi Quinn have all said consistently that the Government needs to change tack," said Mr Martin.

“We would prefer is some of the Ministers were as vocal about Alan Shatter.”

Mr Martin also defended his claim that Minister for the Environment Phil Hogan's local elections reform were an "example of good old-fashioned gerrymandering" designed to maximise Fine Gael and Labour seats in the local elections.

He said his attack had been directed at Mr Hogan and not at the independent commission, chaired by professor Gary Murphy, which had effected the changes.

Mr Martin said it was the terms of reference drawn up by Mr Hogan which had resulted in the change, where the size of local electoral areas were increased from a maximum of six seats to ten seats.

“These very large local electoral areas were designed for safety. In 35 years I have never seen such skewed terms of reference.”

“It’s not in any shape or form related to the Commission. It’s the terms of reference and how they were skewed by the Minister,” he said.