Former British Prime Minister Tony Blair was criticised over a claim that the current generation of political leaders is to blame for the violence engulfing Iraq.
He said that the refusal last year to intervene in Syria's civil war had created the conditions for the al-Qaeda aligned Isis movement to flourish in that country before advancing into Iraq's major cities.
The former Prime Minister insisted that his decision to intervene in Iraq in 2003 was not the cause of the fresh wave of bloodshed. The turmoil across the region has been caused by the Arab Spring, Blair said, which would have swept Saddam from power and caused chaos if Britain and the United States had not intervened in 2003.
He called for air strikes or drone assaults, saying that the Isis fighters posed a threat to British national security. "They are going to pull us into this whether we like it or not," he said.
The claims were met with ridicule from former allies and from MPs who voted against last year's proposed strikes on Syrian President Bashar al-Assad's regime.
Backbench Conservative John Baron who led opposition to the strikes, said Blair's analysis of the crisis was "wrong".
"There is no doubt we went to war in Iraq on a false premise and made grave errors in the immediate aftermath in leaving a power vacuum. A large part of the troubles today can be traced back to that period."
Lord John Prescott, the former Labour deputy prime minister, said: "Put on a white sheet and a red cross and we are back to the Crusades. It is all about religion. In these countries it has gone on for a thousand years."
Former Foreign Secretary Sir Malcolm Rifkind said: "Tony Blair is preoccupied with the assumption that people will say that he, his actions, had at least some part in this."