Christie Brinkley's ex husband Peter Cook has spoken of his regret of the affair that ended his marriage. Brinkley filed for divorce after learning Cook had had an affair with an 18-year-old in 2004.

During a candid interview with Barbara Walters on ABC show 20/20, which aired in the U.S. on Friday, Cook admits he behaved like a "cowardly idiot".

He tells Walters, "I was a great father, a great husband. I failed as a human being. I failed myself.

"Christie is mad at me. She's entitled to be mad at me. I'm an idiot. I made a mistake."

Cook claims he knew his marriage was over when he began seeking attention from someone else.

He says, "I think the emotional aspect of our lives had changed. I think we were both feeling more like we were living with a brother and sister than a life partner.

"I realized my needs hadn't been taken care of, and I took the coward's way out and had an affair instead of approaching my wife and saying, 'Ya know what? I'm not happy.'

He adds, "I wanted a little acknowledgment, a little attention, a little thank you every now and then for my efforts, for the amount of time I took to care for her and my family, for the wealth I was building. Just the tremendous amount of work I was putting into my family."

The interview - which was taped earlier this week - has angered Brinkley, who failed in her attempt to secure a restraining order against him, which would have prevented him contacting the couple's two children.

She claims that by opening up about their marriage problems, he breached a confidentiality agreement in their divorce which they settled on following a bitter public trial over the summer.

Their divorce was finalized in Suffolk County, New York on October 3.

(This news article provided by World Entertainment News Network)