The SDLP would be making a grave error if it signed up to a voluntary coalition without Sinn Féin, Martin McGuinness warned today.
Following SDLP MP Eddie McGrady's recent comments that the party should consider a voluntary coalition with the Reverend Ian Paisley's Democratic Unionists, Mr McGuinness said the SDLP should think carefully about how the nationalist community would respond to such a move.
The Mid-Ulster MP said: "If the SDLP in the form of Eddie McGrady or their deputy leader Alasdair McDonnell is thinking going down this road, they would be ill advised to move away from the Good Friday Agreement.
"Any such move would be rejected by the nationalist and republican electorate and they should think very carefully about doing the bidding of the Democratic Unionist Party.
"They should think carefully about doing the bidding of those opposed to power sharing, human rights and equality."
Last month, the Taoiseach, Mr Ahern, and the British Prime Minister, Mr Tony Blair, felt they had come agonisingly close to securing a landmark deal with Sinn Féin and the DUP which could restore power sharing at Stormont and see republicans abandon paramilitarism and criminality forever.
However the deal stumbled over the IRA's refusal to allow future acts of disarmament to be photographed - a key demand of the DUP.
Any lingering hopes that power sharing could be restored before the next General Election were shattered when Northern Ireland Chief Constable Hugh Orde said he believed the IRA carried out the Stg £26.5 million raid on the Northern Bank in Belfast before Christmas.
The DUP believes a voluntary coalition involving it, the SDLP and the cross community Alliance Party offers the best hope of stable devolved government, arguing such a system already operates successfully in Scotland.
However if that is not possible, the DUP has also proposed that the 11 government departments should be handed over to the Assembly to run, with Stormont committees, rather than ministers, taking key decisions.
In its proposals, the SDLP has suggested that a team of commissioners drawn from civic society should run the government departments under Assembly scrutiny until MLAs are able to become ministers.
Both plans have been rejected, however, by David Trimble's Ulster Unionists. Mr McGuinness said today the only way forward for Northern Ireland was inclusive power-sharing government.
The former Stormont Education Minister said Sinn Fein would also oppose any move to withhold House of Commons allowances from the party.
Last Thursday, Conservative leader Michael Howard signed up to a DUP early day motion at Westminster calling for the move.
"Any attempt to remove the entitlements of elected representatives will impact on their ability to represent the constituencies that elected them," the Mid Ulster MP said.
"I would consider any such move against Sinn Fein's four MPs as a direct attack on our democratic rights and entitlements. That would be unacceptable."