A meeting between Irish premier Bertie Ahern and a loyalist delegation which included UDA leaders has taken place.
The UPRG's David Nicholl (right) said they would work for calm
The meeting in Dublin was held to discuss current initiatives to restore power-sharing by 24 November.
The Ulster Political Research Group said Mr Ahern told them there would be no joint-governmental authority over NI if Stormont was not reconvened.
A UPRG spokesman said they would now work within the loyalist community to maintain calm.
David Nicholl, of the UPRG, which provides political analysis to the UDA, said: "We told the taoiseach that we would work within our particular constituency of loyalism to keep the calm.
"(We want) to persuade people there is no sell-out plan, that there is no betrayal, that there will be no imposition of any further agreement.
"There is one agreement. People must sign up to it."
Bertie Ahern said the meeting had been positive and focused
Mr Nicholl also said the taoiseach had given them assurances there would be "no imposition of an Anglo-Irish (Agreement) mark two".
"The Good Friday Agreement is the only way forward and we welcome all the support that he has given us on our journey and transformation as well and we look forward to working with him in the future," he said.
It is understood similar concerns were expressed at a meeting between a loyalist delegation and Secretary of State Peter Hain at Stormont on Monday night.
Referring to a statement made by DUP leader Ian Paisley on Wednesday that he would never share power with Sinn Fein, Mr Nicholl said it should be viewed in light of the fact that he was addressing an Independent Orange Order gathering.
"It is the same rhetoric we have heard as loyalists for the past 35 years," he said.
"What we would say in relation to that is, we have marched up the hill manys a time, and we have been let down manys a time.
"But loyalism is not going to fill the grave or fill prisons for the next 35 years on anyone's behalf.
"If there is blood to be spilled then let Dr Paisley spill his own blood, because it will not be our bodies he is climbing over."
Mr Ahern described the meeting as "positive and focused".
He said the goal was the restoration of the Northern Ireland Assembly and Stormont executive by 24 November and that this was achievable, if the will was there to do so.
The taoiseach said if this was not achieved, the Irish and British governments would work together to move forward with the implementation of the Agreement.
'Nothing to fear'
He stressed the two governments' purpose was to protect the benefits of the Agreement and loyalism had nothing to fear in this.
Mr Ahern said relationships had been twisted and blighted for far too long and everyone had to make an effort to get it right for the future.
DUP MP Jeffrey Donaldson said the UPRG had "no political mandate" and should respect his party's "huge mandate from the unionist community".
"We would call on the UPRG, instead of attacking fellow unionists, to use their mandate to bring about some movement on the part of the Ulster Defence Association in terms of ending criminality and terrorism and bringing about the decommissioning of weapons," he said.
A Sinn Fein spokesman said the party welcomed the fact the dialogue had taken place.
He called for the UPRG to work to bring about "an end to attacks on Catholics, an end to drug dealing and an effort to engage with the Independent International Commission On Decommissioning".