Newt Gingrich on Thursday denied his ex-wife’s contention that he asked her for an “open marriage” and, in the process, laid into the media for focusing on the issue.

In a remarkable exchange with CNN’s John King at the outset of Thursday’s South Carolina debate, Gingrich said the network and its competitors should not be covering the allegations leveled by his ex-wife.

“I am appalled that you would begin a presidential debate on a topic like this,” Gingrich said when King presented him with a chance to respond to his second wife, Marianne.

Gingrich said the line of questioning was “as close to despicable as anything I can imagine.”

“I am frankly astounded that CNN would take trash like that and use it to open a presidential debate,” he said.

Before he was done, though, Gingrich did respond directly to his ex-wife’s allegations for the first time, issuing a blanket denial.

“The story is false,” he said.

ABC News on Thursday posted excerpts from an interview with Marianne Gingrich that is set to air this evening on the network’s “Nightline” program, in which Marianne says that, at the tail end of her marriage to Newt, he asked her for an “open marriage.” She said she declined.

When news broke Wednesday that Marianne Gingrich had sat down for an interview, Gingrich’s two daughters (who are not from his marriage to Marianne) issued a statement urging the media to turn its focus elsewhere.

ABC has resisted calls to delay the airing of the interview until after the South Carolina primary, which will be held Saturday.

Gingrich didn’t seem to hold a grudge against King though, saying at the conclusion of the debate that King “did a great job.”