Sarah O’Connor, whose brother Sergeant Bob O’Connor was killed in 2005, said Mr Blair should have come to speak to bereaved families in person at the report’s release.
She said: “Personally for myself I feel anger that heeling, that 11 and a half years I’ve worked for, I have gone back to that time when I learnt that my brother had been killed.
“There one terrorist in this world, the world needs to be aware of and his name is Tony Blair. The world’s worst terrorist.”
Ms O’Connor was joined on a panel of families by Roger Bacon, who said a legal challenge against the legality and decision making behind the war is on the table.
At a press conference in London following the release of he report, he said: “We were proud of our husbands, sons and daughters signed up to serve our country. But we cannot be proud of the way our Government mistreated them.
“We must use this report to make sure that all parts of the Iraq war fiasco are never repeated again.”
“We call on the British Government to immediately to honour the report’s findings to ensure the political process by which our country decides to go to war is never again twisted.”
He said the families reserve the right to call specific parties to answer for their actions in the courts “if such a process is felt to be right”.
Mr Bacon and his wife Maureen lost their son Matthew, 34, a major in the Intelligence Corps, when his Snatch Land Rover was hit by an improvised explosive device (IED) in Basra on 11 September 2005.
He said: “Never again must so many mistakes be allowed to sacrifice British lives, and lead to the destruction of a country for no positive end.”
Families were visibly upset as they sat on the panel taking questions from the media. Audience members also looked shaken by the findings and tissues were passed around the room.
Lawyer Matthew Jury said all options would be considered in terms of legal action as the report appears to confirm that their loved ones died “unnecessarily without just cause or purpose”.