Relatives of the victims of the Omagh bombings today said they had received assurances from prime minister Tony Blair that no one connected with the 1998 atrocity would be granted an amnesty even if they are members of Sinn Fein or the IRA.
Representatives of the 29 victims and those injured in the blast held talks lasting 45 minutes with Mr Blair at 10 Downing Street to press their case for a full cross-border public inquiry.
Speaking after the talks, they said that the prime minister had told them an inquiry would be impossible until current civil and criminal court cases arising from the blast were completed, but did not rule out meeting their request after that point.
Michael Gallagher, whose son Aiden (21) was killed in the no-warning attack, said Mr Blair had been "very supportive and as helpful as he could have been".
But he said Mr Blair did not seem to be "up to speed" with some details of the inquiry - something that was acceptable, given the complexity of the case.
He said Mr Blair had offered the assistance of a senior civil servant to help the families with their work and had promised to look at a dossier which they had prepared making the case for an inquiry.
Victor Barker, from Surrey, whose 12-year-old son James died at Omagh, said that the families had secured an unequivocal promise that there would be no amnesty for those responsible.
"The assurance we sought was that if there were any members of Sinn Fein or IRA that were involved in the Omagh bomb, whether or not they are on the run, they would receive no amnesty in respect of the 1998 atrocity in Omagh," said Mr Barker.
"That assurance was given us unequivocally." Mr Gallagher said: "I think there are certain undertakings that the Prime Minister has given this afternoon that we will hold him to, and I have no doubt that he will carry them through.
"I think we had a fair hearing and we put the case strongly, so we are very happy with the outcome of the meeting. "We are realistic enough to know that we would never have a public inquiry in any case until the current cases are dealt with."
Mr Gallagher said that the families were determined to press on with their fight for the truth, no matter how long it took.