Dick Cheney has told ABC News that John McCain's choice of Sarah Palin as his running mate for the 2008 Republican presidential ticket was "a mistake".

The man who served as Vice-President of the United States from 2000 to 2008, and who underwent a heart transplant in March, was interviewed at his Wyoming ranch.

The topic of Palin came up when Cheney was asked to speculate on whom Mitt Romney will choose as his vice-presidential candidate on the 2012 ticket.

When asked how important it was that Romney go about choosing a running mate differently than McCain did, Cheney replied, "Pretty Important. That one I don't think was well-handled."

Cheney, who served on the vetting committee when both Gerald Ford and George W. Bush were looking for running mates, said that during the selection process, there was always a long list of potential candidates and a short list. He implied that the long list was always largely a smoke screen.

"That was the big list. It was easy to get on the big list. The tough part is the small list, the one that's really under active consideration. And the test of the small list has to be: Is this person capable of being President of the United States? And that's usually a very, very short list."

Cheney was asked how important it was that the person be able to bring states or apply to certain demographics.

"Those are important issues but they should never be allowed to override that first proposition, and I think that that was one of the problems McCain had," he replied.

Cheney said that he likes Sarah Palin and that she was an "attractive candidate", but added, "I don't think she passed that test."

He mentioned that she had only been Governor of Alaska for two years when she was nominated for Vice-President.  

"I think that was a mistake," he said.

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