Former US vice president Dick Cheney says former president Jimmy Carter might have been a better president than Barack Obama. In an interview with CNN on Tuesday, Cheney once again criticized Obama’s policies, calling him the worst president of his lifetime. "Jimmy Carter might have been a better president than Barack Obama, and I didn't think I would ever say that," Cheney said. "I think he is the worst president of my lifetime. I fundamentally disagree with him. I think he's doing a lot of things wrong," he added. He also rejected Obama’s impeachment, saying he was "not prepared at this point to call for the impeachment of the president." Cheney defended the Bush administration’s Iraq policy. "By the time we left office, Iraq was in relatively good shape," he said. "The plan was to have a stay-behind force that could continue to train the Iraqis and provide capabilities they didn't have themselves, intelligence, air and so forth. And what happened was, that stay-behind agreement was never negotiated.” “Obama's failure to provide for a stay-behind force is what created the havoc we see in Iraq today," Cheney continued.