McCain, 34, exploded at producers Monday over what she claimed was "unfair treatment" from her co-host Behar, 76.
The brawl began after Behar opened up a discussion about Senator Amy Klobuchar's 2020 presidential bid. As Behar mentioned President Donald Trump's tweet about Klobuchar, McCain jumped in and was immediately cut off.
"Can I say something now? Is that ok? Do I have permission to speak now on Amy Klobuchar now? We're all good?" McCain said to Behar moments later.
A sulking McCain, who sources say is "losing patience" with the program, became visibly offended again. "Alright, nope, nope, by all means, keep going, Joy," she told Behar.
"If you're going to have a hissy fit, we can't continue," Behar responded.
"Producers told Meghan that she can't sulk and sit in silence," said the snitch. "They have told her that this is a tv show and a talk show and the hosts must talk. They cannot sit in silence, upset and pouting."
After Monday's episode wrapped, the source said McCain "blew up" at producers for repeatedly taking Behar's side.
"She's upset about the unfair treatment," said the source.
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