Washington: Acknowledging that his affair with the White House intern Monica Lewinsky was "a terrible moral error", former US president Bill Clinton said that it almost destroyed his marriage and threatened to alienate his daughter.

However, he said in an interview to CBS television that he regards his battle against the impeachment that followed the revelation of affair "a badge of honour".

The former president said the disclosure of his relationship with Lewinsky put him "in the doghouse" with his wife Hillary Rodham Clinton, now a Senator.

Hillary, he said, needed time to decide whether to stay married with him. The affair also threatened to alienate his daughter Chelsea.

However, Clinton called the Republican attempt to drive him from office "an abuse of power", saying, "I didn't quit. I never thought of resigning and I stood up to it and beat it back. The whole battle was a badge of honour. I don't see it as a stain, because it was illegitimate."

In a tone of sadness and self-reproach, Clinton said of the affair, "I think I did something for the worst possible reason -- just because I could. I think that is just about the most morally indefensible reason that anybody could have for doing anything. There are lots of sophisticated explanations, more complicated psychological explanations, but none of them are an excuse."