The DUP delegation to the Haass talks said it had laid down some "clear red lines" over issues such as flags and dealing with the past.
The talks team, including Lagan Valley MP Jeffrey Donaldson and Orange Order chaplain Mervyn Gibson, said they had made the party's position clear on the suggestion that the Irish tricolour could fly over Stormont on certain occasions.
The Belfast Telegraph yesterday revealed the suggestion by the Haass team that the Irish flag could be flown on occasions such as a State visit by the Irish President or an official visit by the Taoiseach – which Mr Donaldson said was "totally unacceptable".
Mr Donaldson added: "There is no question of anything that looks like or sounds like an amnesty, (and) I don't think immunity is the correct term of use." He insisted there would be a "firewall" between the proposed new single Historical Enquiries Unit which can decide on prosecutions and the planned Independent Commission for the Recovery/Retrieval of Information, which it is understood could in some circumstances be allowed to use limited immunity.
The model suggesting "targeted use immunity" which can specify that statements given cannot be used in any court proceedings was also revealed in the Belfast Telegraph.
On the most thorny issue, of flags, suggestions that a decision on how many days the Union flag is displayed could be left to the 11 new super councils have also been met with unionist disdain.
Sinn Fein's Gerry Kelly, however, predicted that, with political will, an agreement could be signed up to within 48 hours.
The SDLP's Alex Attwood argued that leaks to the Belfast Telegraph were harming the process.