Unionist leaders were afraid of cutting a deal during the Haass talks unless they had the approval of hardline loyalists, it has been claimed.
Flag protester Jamie Bryson claimed the conclusion of the talks in failure represented a victory for loyalism.
He even claimed to have been shown negotiation documents in order to get his opinion during the talks as the DUP and UUP sought to ensure loyalist approval.
"I think they are petrified, really scared," he claimed.
"The derailing, for the time being, of the Haass process is a victory for those of us within the Protestant community that are fed up with the continuous appeasement of Sinn Fein/IRA and who are opposed to the peace process in its current format.
"That is not an opposition to peace, it is opposition to peace at any price.
"The DUP/UUP are no doubt looking over their shoulders at the coming elections.
"It is no secret that the DUP are becoming increasingly concerned about a growing anti-Agreement movement which has grown from a tiny minority of us to a much more sizeable number."
Talks chairman Dr Richard Haass had asked parties not to reveal the contents of confidential proposals during the talks, not allowing delegates to take paper away and even banning mobile phones.
It is understood that the DUP and UUP consulted hardliners outside the talks on issues including:
• The classification of the poppy as a contentious symbol;
• A parading code of conduct that would have banned loyalist bands named after paramilitaries;
• The granting of more powers to the Office of the First and deputy First Minister over parades, and
• Proposals for the flying of flags and dealing with the past.
The Belfast Telegraph has been told that the DUP and UUP feared that if anti-Agreement unionists – such as Mr Bryson, victims campaigner Willie Frazer, TUV leader Jim Allister and some victims – could not be convinced, then a deal could not be struck.
Mr Frazer claimed the talks were the first where victims were consulted, and also the first where the DUP and UUP worked together.
"The victims are positive (about the Haass talks outcome), as long as the politicians stick to their word. For the first time the victims have been included," he said.
"No-one is more vocal than us when things haven't been done, so it is right to give credit where credit is due."
Yesterday marked the annual memorial service to 10 Protestant workmen killed by the IRA at Kingsmills. Pastor Barrie Halliday, who led the commemoration, described the Haass talks as a victory for victims.
He said the families felt that, unlike in previous years, they had not been forgotten about. He also revealed that the families would be meeting Secretary of State Theresa Villiers at Hillsborough Castle on Wednesday.
Mr Halliday said they now have fresh hopes of a public inquiry into the Kingsmills atrocity.
"We are hopeful with Haass that if the past is looked at, we will get some kind of inquiry and the truth finally brought out," he said.
Unionist negotiators did not deny that Mr Bryson had been shown documents.
DUP negotiator Jeffrey Donaldson said he was not aware of it, but confirmed that Mr Frazer and others were kept informed.
Ulster Unionist negotiator Tom Elliott said he had no knowledge of Mr Bryson being shown the documents. "I am not saying it wasn't happening, but not that I am aware of," he said.
The Ulster Unionist Executive is meeting tonight to decide its position on the Haass document.
The DUP and Orange Order are expected to hold meetings later in the week to decide on their position.