US Secretary of State Condoleezza Rice has denied former President Bill Clinton's claim that he did more than his successors to stop Osama Bin Laden.
Bill Clinton: "They had eight months... they did not try"
Mr Clinton said the Bush administration had not tried to tackle the al-Qaeda leader prior to the 9/11 attacks.
Ms Rice, who was White House national security adviser at the time of 9/11, said this was "flatly false".
She also disputed the former president's claim that he left behind a comprehensive plan to fight al-Qaeda.
Ms Rice made her comments during a meeting with editors and reporters at the New York Post.
It came after Mr Clinton, in a heated interview on Fox News, defended his handling of the threat posed by Bin Laden and said he had "worked hard" to have the al-Qaeda leader killed.
"That's the difference in me and some, including all of the right-wingers who are attacking me now," Mr Clinton said.
"They ridiculed me for trying. They had eight months to try, they did not try."
Ms Rice responded: "What we did in the eight months was at least as aggressive as what the Clinton administration did in the preceding years.
"The notion somehow for eight months the Bush administration sat there and didn't do that is just flatly false - and I think the 9/11 commission understood that."
She also disputed Mr Clinton's statement that he "left a comprehensive anti-terror strategy" for incoming officials when he left office, including "battle plans" to go into Afghanistan, overthrow the Taleban regime and launch a full-scale search for Bin Laden.
"We were not left a comprehensive strategy to fight al-Qaeda," she said.
"For instance, big pieces were missing, like an approach to Pakistan that might work, because without Pakistan you weren't going to get Afghanistan."
And she went on to question the value of the entire argument.
"I think this is not a very fruitful discussion," she said.
"We've been through it. The 9/11 commission has turned over every rock and we know exactly what they said."