In the crucial weekend before to the final breakdown of diplomacy in March, Mr Clinton was a guest of Mr Blair's at Chequers where the pair discussed the crisis.
Mr Blair was battling to persuade the Chilean president Ricardo Lagos - a key figure on the security council - to back a second UN resolution setting a new deadline for Saddam to co-operate fully with the UN or face military action.
Three days after his Chequers meeting, Mr Clinton made a rare public appeal to his successor, George Bush, to give the UN weapons inspectors more time.
Mr Blair and Mr Clinton met at least three times to discuss the war, underlining the extent to which Mr Blair rates Mr Clinton's analytical powers, despite the bond of trust he has also formed with the Republican White House.
Three days after his Chequers meeting, Mr Clinton made a rare public appeal to his successor, George Bush, to give the UN weapons inspectors more time.