Stormont crisis talks: PSNI Chief Constable George Hamilton asked to attend
Northern Ireland's most senior police officer could be summoned before crisis talks aimed at saving the region's crisis-hit political institutions.
If cross-party negotiations fail, it could be a decade before devolved power-sharing in Belfast is restored, First Minister Peter Robinson said.
The warning came as the Ulster Unionist Party (UUP) said it would not take part in crunch talks unless the status of the IRA was resolved.
Mr Robinson said: "If the Assembly and Executive falls we are probably talking about the best part of a decade before it would ever be revived. These are extremely important talks."
The ministerial Executive at Stormont has been under threat of collapse since police said IRA members were involved in the murder of Kevin McGuigan in east Belfast last month.
Police believe Mr McGuigan was killed by individual members of the Provisional IRA in revenge for the death of prominent republican Gerard "Jock" Davison in May.
Although Police Service of Northern Ireland (PSNI) Chief Constable George Hamilton has insisted the IRA is not back on a war footing, disclosure that the organisation still exists has rocked the political establishment.
Discussions, scheduled to last for four to six weeks, were launched by the British and Irish governments at Stormont House.
Mr Robinson added: "The request that was put today to the government for the chief constable to come to the talks process was made by the DUP. We will be there to hear him.
"The issues that have to be dealt with all have to be dealt with before anything is agreed by us. If the issue of the paramilitary involvement is not resolved, then there will be no overall agreement."
Unionists have pressed for measures including a temporary suspension of the Assembly to allow space for negotiations which have begun between the five main Executive parties.
But, outlining the British Government's position in a speech to the House of Commons, Northern Ireland Secretary Theresa Villiers said the time was not right for direct rule.
She said: "The Government does not feel that the time would be right to suspend the institutions at this stage and under these circumstances.
"If the circumstances were to change in the future, we would of course need to look at all our options."
On Monday, the Democratic Unionist Party (DUP), Northern Ireland's largest party, said there would be no further routine meetings of the ministerial Executive until the latest crisis was resolved.
The Ulster Unionist Party has withdrawn its only Executive minister Danny Kennedy, claiming it could no longer trust republicans.
Leader Mike Nesbitt said they would not discuss the Stormont House Agreement, which tackled outstanding peace process issues, until the issue of paramilitarism had been resolved.
After the negotiations, he said: "This is the issue and the only issue that we will speak on. We will consider going into the session which deals with the IRA."
He later added: "We took a principled stand to withdraw from the Northern Ireland Executive on the issue of Sinn Fein's lack of credibility.
"On that basis, we will remain consistent and not participate in political talks unless and until this matter is resolved."