A source tells Us Weekly that Nicki Minaj's confrontation with Miley Cyrus was not at all planned, and that the rapper's rage was "very real" Credit: Kevin Mazur/MTV1415/WireImage.com; Michael Tran/FilmMagic

Not an act! Nicki Minaj wasn't kidding when she confronted 2015 VMAs hostess Miley Cyrus during the live broadcast on Sunday, Aug. 30. After the "Anaconda" rapper called the pop star a "bitch" for talking about her in the press, some people wondered whether the onstage tiff was part of a pre-planned bit between them. But a source tells Us Weekly that there was nothing fake about Minaj's rage. 

"Nicki was livid with Miley and decided to air her feelings onstage," the insider tells Us of the "Truffle Butter" hitmaker, 32, who was angry over an interview Cyrus gave to the New York Times. "The anger was very real and not a pre-planned bit at all."

In fact, the source says, MTV staffers "had to be sure Nicki and Miley didn't cross paths for the rest of the evening because they were legitimately worried about a confrontation happening."

As previously reported, Minaj was accepting the Moonman for Best Hip Hop Video for "Anaconda" when the face-off went down on Sunday. After saying her requisite thank yous, she turned to Cyrus, 22, and said, "And now...back to this bitch that had a lot to say about me in the press. Miley, what's good?" 

The "Wrecking Ball" songstress looked taken aback for a few seconds before she replied, "Hey, we are all in this industry and we all do interviews and say s--t. Nicki, congratuf--kinglations."

The camera then flashed back to Minaj, who could be seen mouthing, "Don't play with me, bitch!"

The rapper's anger was in response to some comments Cyrus made about Minaj's Twitter feud with Taylor Swift last month. The two had a brief misunderstanding over Minaj's complaints about the Video of the Year nominees, but ultimately made up — and even surprised the VMAs crowd with a joint performance. Click here to see 8 of the craziest moments at the 2015 MTV VMAs.

Asked about the spat by the New York Times last week, Cyrus said she thought Minaj was in the wrong. "I saw that. I didn't really get into it. I know there was some beef," she said. "I don't really know. There's a way to talk to people...What I read sounded very Nicki Minaj, which, if you know Nicki Minaj is not too kind. It's not very polite. I think there's a way you speak to people with openness and love."

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