It's the news Newt Gingrich doesn't want to deal with in the midst of a possible GOP presidential campaign revival.

Marianne Gingrich, the second wife of the former House Speaker, is speaking out to ABC about her former husband's infidelity for the first time since their divorce in 1999.

After Gingrich admitted to her that he had a six year affair with his current wife Callista while she was a congressional aide, Marianne told ABC that he wanted to have both a spouse and a mistress.

"And I just stared at him and he said, 'Callista doesn't care what I do,'" she said. "He wanted an open marriage and I refused."

Gingrich married Marianne in 1981 after divorcing his first wife Jackie while she was being treated for cancer. Their marriage lasted until Gingrich sought for a divorce after Marianne was diagnosed with multiple sclerosis.

On NBC's Today Thursday morning, Newt Gingrich said he would not "say anything negative about Marianne."

The full interview is scheduled to air on ABC's Nightline Thursday evening at 11:35 P.M.

WATCH: Video from ABC, which was broadcast on January 19, 2012.

video platformvideo managementvideo solutionsvideo player