Minister for Foreign Affairs Dermot Ahern warned tonight that if the North's parties fail to honour the St Andrews power sharing plan that the Irish and British governments will reluctantly implement their 'Plan B' for government.
Speaking in the Dáil ahead of tomorrow's Assembly at Stormont where the DUP and Sinn Féin are expected to name their choices for First and Deputy First Minister, Mr Ahern said the alternative plan was not the preferred option but confirmed "if we fall at any hurdle, then we will go to Plan B."
"We want to see devolved government restored to Northern Ireland and we believe leadership is needed from the DUP and Sinn Féin to achieve this."
Mr Ahern was commenting after a frantic round of behind-the-scenes negotiations to ensure the DUP will tomorrow indicate their intention to nominate the Rev Ian Paisley as First Minister alongside Sinn Féin's Martin McGuinness as Deputy First Minister.
Sinn Fein president Gerry Adams today called on the British and Irish governments to implement their Plan B if the DUP failed to indicate tomorrow their nominee for First Minister.
"At the very, very minimum, at the very least, there has to be the nomination of the First and Deputy First Ministers," he said in Dublin. "If there are not nominations tomorrow, then sin e (that's it). That's our very, very strong view."
The West Belfast MP added if the DUP did not indicate its choice for first minister, "the governments need to move smartly into the partnership arrangements which they signalled up in Scotland".
Originally Northern Ireland Secretary Peter Hain set November 24 as the deadline for the actual nomination of Mr Paisley and Mr McGuinness as Shadow First and Deputy First Ministers.
Sinn Féin and the DUP are now expected to merely indicate at tomorrow's meeting who will be their choices. Concerns have been raised that the DUP may not signal who their nominee will be because of Sinn Féin's position on policing.
However, the prospect of Mr Paisley heading a power sharing administration at Stormont with Martin McGuinness has also unnerved colleagues in his church.
Two Free Presbyterian ministers, the Rev Ivan Foster and the Rev Wesley McDowell, broke ranks today to warn him against the move.
The Rev McDowell warned tonight: "People are concerned about a relationship with Martin McGuinness.
"Even if Martin McGuinness were to go to the police supporting the police, supporting the process of law and order totally in Northern Ireland , he is still perceived to be a man of blood and we could not stomach a man of blood in a place of authority in Northern Ireland .
"We will follow the path which we believe is right before the Lord and we do not think Dr Paisley would expect us to do otherwise."