John Edwards‘ mistress Rielle Hunter is "ready for her close-up" with her first national TV interview since the cheating scandal wrecked his career, The ENQUIRER has learned exclusively.

In a startling change of heart, Rielle Hunter has decided to face the cameras and has narrowed her choice of interviewer to either "ABC News" correspondents Diane Sawyer or Barbara Walters, say sources.

"Rielle had previously assured John she wasn’t going to spill the beans," said a close source. "But she’s changed her tune after thinking Elizabeth Edwards might disparage her in the upcoming interview she’s already taped with Oprah Winfrey.

"The interview will be broadcast in mid-May to coincide with the publication of Elizabeth’s new book in which she’s likely to address the affair."

As a result, a behind-the-scenes war of words is breaking out between Rielle and Elizabeth.

"Rielle’s decided she’s not going to sit back while Edwards’ wife gives her side of the story," said the close source. "As much as John hates it, he’s defenseless to stop either woman from saying what she wants. It’s now erupted into a war between his wife and his former mistress over who will have the last word in what could be dueling TV interviews."

Rielle intensified talks with the ABC superstars in early April in preparation for going in front of the cameras.

"No deal is done, but Rielle seems to favor Barbara Walters over Diane because Barbara admitted recently she engaged in a long-ago affair," said the close source. "This makes Rielle believe Barbara will show her more compassion than Diane would."

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