The stars of Celebrity Apprentice 4 are hard at work trying to impress Donald Trump and RadarOnline.com has exclusively learned that Real Housewives of Atlanta star NeNe Leakes is already causing havoc with her fellow cast mates.

“NeNe is causing trouble on the show,” a source told RadarOnline.com.  “She showed up late to filming and that didn’t win her any friends.”

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According to a source, when the cast list was first leaked and NeNe was mentioned, she started making phone calls and telling people that she was one of the celebrities on the show.

The person who NeNe has been fighting with?  Star Jones, formerly from The View.

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Celebrity Apprentice 4 contestant and Real Housewives of Atlanta star NeNe Leakes has struck-up a friendship with the reality show’s former ‘firecracker contestant’ Omarosa Stallworth, RadarOnline.com can reveal.

And Omarosa – who became the woman America loved-to-hate after appearing on Donald Trump’s Apprentice in 2004 – has been schooling NeNe on how to get ahead on the show.

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Maybe that’s why reports have already surfaced that NeNe is displaying some diva-like behavior after the new series recently started taping - it includes other celebrities like Dionne Warwick, La Toya Jackson, and Star Jones.

A source told RadarOnline.com: “NeNe and Omarosa have become friends and NeNe is determined to assert herself among the other contestants and to do well on the show.