Martin accuses Kenny of failure of leadership on Northern crisis

Fianna Fáil Leader Micheál Martin said Mr Kenny had shown "a lack of leadership".

"This is an emergency and it will not wait until after the Government returns from its summer holidays," Mr Martin said as he urged the Taoiseach to act immediately.

The Government reacted coolly to the Fianna Fáil leader's comments, however.

"The Taoiseach has been kept fully apprised of all the developments on this issue. A meeting has been set up between ministers Flanagan and Fitzgerald and Northern Ireland secretary Theresa Villiers, and Mr Kenny will continue to assess the situation," a government spokeswoman said.

Mr Kenny (pictured) is expected to return from holiday next Monday and attend a cabinet meeting on Wednesday. Officials said he had been working in the earlier part of August and continued to keep tabs on events even while on a break.

The continuing crisis arose after the PSNI chief constable, George Hamilton, last Saturday delivered his assessment that IRA structures still exist.

Mr Hamilton said his officers were following a line of inquiry as to whether Provisional IRA members were involved in the murder of Kevin McGuigan in Belfast on August 12.

The Fianna Fáil leader rejected Mr Kenny's officials' explanations of his stance on the issue.

"The Taoiseach had no problem tweeting his positive reaction to employment figures this week. But he has made no comment and has taken no action to address the political crisis that is causing grave damage to the peace process on our island," Mr Martin said.

"I am calling on Enda Kenny to make immediate contact with the British Prime Minister David Cameron to set up a bi-lateral meeting as soon as possible.

"As co-guarantors of the Good Friday Agreement, both governments have a special role in overcoming this threat to the peace process and need to take real action," the Fianna Fáil leader added.

Ulster Unionist Party (UUP) leader Mike Nesbitt directly challenged Sinn Féin's insistence that the IRA does not exist. Speaking ahead of today's meeting of his party's executive, he said Sinn Féin's position on the IRA "lacked credibility".

The UUP executive meeting is set to endorse Mr Nesbitt's proposal to withdraw Danny Kennedy, its only member of the Stormont power-sharing executive. Mr Nesbitt said Sinn Féin was creating a vacuum of disbelief and it was very hard to work with the party.

"It is statements from Sinn Féin which lack credibility. The chief constable says the IRA exists. Gerry Adams and Martin McGuinness say the IRA does not exist.

"I don't believe the Sinn Féin leadership. If we can address that, we can move on. If they are going to insist the IRA does not exist, we cannot move on because there is no trust and without trust there is nothing," he told RTÉ radio.

Mr Nesbitt said progress could be made if Gerry Adams, as Sinn Féin president, or Martin McGuinness, as Northern Ireland Deputy First Minister, could admit the IRA still exists - but did not exist for "the old reasons".