The crooner, who is a World War II veteran, discussed his political views with Howard Stern this week, insisting that the US foreign policy played a role in inspiring the terrorist strikes.
"They flew the plane in, but we caused it… We were bombing them, and they told us to stop," Bennett told the radio host.
Bennett objected to Stern's use of the word "terrorists" when describing the 9/11 hijackers, saying: "Who are the terrorists? Are we the terrorists, or are they the terrorists? Two wrongs don't make a right."
The singer also claimed that President George W Bush once told him he regretted starting the Iraq War during a Kennedy Centre gala.
"He told me personally that night that, he said, 'I think I made a mistake'," Bennett recalled.
However, a spokesperson for Bush has since dismissed Bennett's account as "flatly wrong", adding to NBC: "President Bush never said that to Tony Bennett or anyone else."
Bennett has issued a public apology for his remarks on 9/11, saying: "There is simply no excuse for terrorism and the murder of the nearly 3,000 innocent victims of the 9/11 attacks on our country.
"My life experiences - ranging from the Battle of the Bulge to marching with Martin Luther King - made me a lifelong humanist and pacifist, and reinforced my belief that violence begets violence and that war is the lowest form of human behaviour."
Bennett concluded: "I am sorry if my statements suggested anything other than an expression of my love for my country, my hope for humanity and my desire for peace throughout the world."
This week, Bennett released his latest album Duets II, which features collaborations with Lady GaGa, John Mayer and the late Amy Winehouse.
Watch Tony Bennett discuss his political beliefs with Howard Stern below: