Former U.S. President Jimmy Carter has lashed out at George W. Bush's presidency, calling his administration "the worst in history" in international relations.

"I think as far as the adverse impact on the nation around the world, this administration has been the worst in history," said Carter in an interview with The Arkansas Democrat-Gazette released Saturday.

The Nobel Peace Prize winner in 2002 came down hard on the Iraq war, saying Bush had taken a "radical departure from all previous administration policies."

"We now have endorsed the concept of pre-emptive war where we go to war with another nation militarily, even though our own security is not directly threatened, if we want to change the regime there or if we fear that some time in the future our security might be endangered," he said.

Carter criticized Bush for having "zero peace talks" in Israel. Carter also said the administration "abandoned or directly refuted" every negotiated nuclear arms agreement, as well as environmental efforts by other presidents.

The White House declined to comment on Saturday, but on Sunday fired back.

"I think it's sad that President Carter's reckless personal criticism is out there," White House spokesman Tony Fratto told reporters. "I think it's unfortunate. And I think he is proving to be increasingly irrelevant with these kinds of comments."

Carter has been an outspoken critic of Bush, but the White House has largely refrained from attacking him in return. Sunday's sharp response marks a departure from the deference that sitting presidents traditionally have shown their predecessors.

In a separate BBC interview Saturday, Carter also lashed out at British prime minister Tony Blair.

"Abominable. Loyal, blind, apparently subservient," Carter said when asked how he would characterize Blair's relationship with Bush.

Carter, who was the U.S. President from 1977-1981, was an outspoken opponent of the invasion of Iraq before it was launched in 2003.

Editor: Yan