The SDLP have refused to indicate whether they would support an “exclusion motion” which could see Sinn Fein stripped of its ministerial positions at Stormont in the wake of the Kevin McGuigan murder revelations.
Earlier this week the PSNI said it believed a range of people – including PIRA members – may have had a role in the murder of Belfast man Mr McGuigan.
Following the announcement, First Minister Peter Robinson threatened to bring an “exclusion motion” before the Assembly reconvenes at the start of September.
The SDLP would not state last night if it would back such a bid.
A spokesman said: “The SDLP believes this situation requires calm heads and calm discussions. We do not deal in hypothetical situations.
“We are meeting the Chief Constable as a matter of urgency to further establish the facts of this case. There are many unanswered questions – among them, was this murder sanctioned, if so by whom, and at what level? The right thing to do is get to the truth of the matter and then make the call.”
UUP member of the Policing Board Ross Hussey said the PSNI’s Thursday statement – which indicated that members of the PIRA cooperated with others in the murder of Mr McGuigan – raises questions of PIRA involvement in other murders and attacks.
He added: “The confirmation that PIRA members were involved in the killing proves that the organisation still exists and still has the ability to act with lethal effect.
“Logic would suggest that there is still an IRA Army Council and a GHQ staff.
“Given this revelation, I believe other PIRA murders and attacks in recent years cannot be ruled out.”
TUV leader Jim Allister said the facts could not be “dressed up”.
“Whatever spin is deployed, the words of the PSNI could not have been clearer,” he said, adding: “Anyone who cannot understand that clearly has a political interest is not understanding.
“Put simply, the IRA exists. They have not decommissioned all their weapons.”
Steven Agnew of the Green Party described the developments as “worrying” and added: “It is unacceptable for a party of government to be linked to an active paramilitary organisation, if, as the PSNI implies, the Provisional IRA is still active. We need to base any decision on evidence rather than speculation.”
Republic of Ireland justice spokesman Niall Collins described PSNI Det Supt Kevin Geddes’ statement as “absolutely chilling”.
He said: “Det Supt Geddes’ choice of language points to a general acceptance among the PSNI that the command structure of the Provisional movement is still in place. In the recent past, Sinn Fein have moved quickly to frustrate uncomfortable PSNI investigations on the basis they judged them to be too ‘political’. It is critically important that in this instance they step back and allow the investigations to continue without disruption.”
Meanwhile, Sinn Fein MLA Gerry Kelly called for “calm heads and political leadership”, saying that political leaders needed to “stand together”.
He added: “The families of Gerard ‘Jock’ Davison and Kevin McGuigan deserve justice and the task of the police is to carry out a thorough investigation. The PSNI need to get on with their investigation and bring to justice those responsible for the killing. “The actions of the criminals responsible for the killings are an attack on all the people of this community.
“This is a time for calm heads and mature political leadership. What is required now is mature leadership from all of our political parties in standing together against criminal gangs trying to bring us back to the past.”
However, Ulster Unionist Fermanagh and South Tyrone MP Tom Elliott said he could have written “the script” for the scenario.
He added: “The finger points at members of the PIRA as being responsible for carrying out a brutal murder and somehow Sinn Fein want us to believe the police are the ones who have done something wrong. We have heard these denials before.
“Sinn Fein must learn that public scrutiny in the aftermath of murder is not anti-peace process.”