EXCLUSIVE: Gayle King 'Facing CBS Showdown Over Norah O'Donnell Return'

Talk that Norah O'Donnell may return to CBS Mornings has host and bitter rival Gayle King "furious" and ready to lay down an ultimatum to execs, according to network sources, RadarOnline.com can reveal.

"Gayle is not happy," an insider shared. "The last thing she wants or needs is to see Norah walk back into that studio. She won't stand for it."

As RadarOnline.com has reported, the two anchors have a long and contentious history, with many saying Norah, 52, was thrilled to leave 71-year-old King behind to take over the CBS News anchor desk after seven contentious years together on the show – and not just because of the prestige of her new position.

Insiders said King was glad to see her go and remade the struggling morning show – naming her own co-hosts in Nate Burleson and Tony Dokoupil.

"Gayle and Norah have years of history," a source told RadarOnline.com. "Putting them back behind the same desk would be like throwing a match into a gasoline can."

But O'Donnell hit hard times after she left the show, enduring terrible ratings as the evening anchor and gaining an internal reputation as a diva, forcing the relocation of her show from New York to Washington, D.C., to be close to her husband's restaurant business.

She was replaced on the anchor desk by since-fired John Dickerson and Maurice DuBois, who then lost the gig to King's pal Dokoupil earlier this year.

But controversial new CBS News Editor-in-Chief Bari Weiss' scorched-earth changes have seen O'Donnell's stock rise again recently – with a new correspondent slot on the renovated 60 Minutes and even fill-in spots on her old show – which insiders said has infuriated old rival King.

With CBS Mornings recently suffering its lowest-rated week ever, averaging a paltry 1.59million viewers, rumors are flying Weiss has plans to completely renovate the show, adding a third host to fill the spot Dokoupil once held, and upsetting King's handcrafted world.