No-one involved in the 1998 Omagh bomb will benefit from an amnesty, the families of the victims have said.
Relatives of the Omagh bomb victims are seeking a judicial inquiry
The relatives were speaking after asking Prime Minister Tony Blair for a cross-border judicial inquiry into the bombing, which claimed 29 lives.
Michael Gallagher, whose son Aiden died in the Real IRA attack, said Mr Blair told them any inquiry would have to follow criminal and civil cases.
"Omagh is such that people can't keep the lid on it forever," he said.
"We will eventually know the truth - but I would like to know it in my lifetime."
Victor Barker, whose son James died in the attack, said they had been assured no-one, including any IRA or Sinn Fein member, involved in the periphery of the bombing would benefit from any amnesty.
"That would include members of Sinn Fein who may or may not have had knowledge of the Omagh bomb or were involved on the periphery of the bomb - even though they are members of Sinn Fein they would not receive amnesty," Mr Barker said.
However, Mr Gallagher said that while he did not feel Mr Blair understood all the complexities of the bombing they felt they had received a fair hearing.
"There are certain undertakings that the prime minister gave this afternoon and we will hold him to and I have no doubt that he will carry them through," he said.
He said that they were "weary" after seven years of campaigning, but that they would continue.
"I feel that some of the people close to the prime minister have been a bit naive in how they have handled the Omagh bomb and they have underestimated the Omagh families' determination to get to the truth," he said.