Robert De Niro has beef with Jay-Z. The actor reportedly gave the rapper a piece of his mind, calling him "rude" at Leonardo DiCaprio’s birthday bash on Nov. 10.

According to Page Six, De Niro reprimanded the rap mogul for not returning the 69-year-old's calls. A source says, “Bob was sitting at a table, and when Jay-Z went over to say hello, De Niro told Jay that he never called him back."

De Niro was overheard at New York's The Darby saying he was trying to get in touch with the Hova about a song he agreed to record for the Tribeca Film Festival. The Oscar winner had reached out to discuss the details, but never heard back from the Brooklyn native.

“Bob wasn’t in any mood to make polite conversation,” an insider says. “He told Jay that if somebody calls you six times, you call them back. It doesn’t matter who you are, that is just rude."

Jay-Z tried to joke about the situation, saying he was terrible with the phone, but De Niro wasn't having it. The source continues, “De Niro kept telling him that he thinks he’s the man, but that he was disrespectful.’ ”

However, another De Niro source told the paper: “It was a low-key private conversation between two people that was apparently overheard. It was not a heated discussion.” Reps for both De Niro and Jay-Z declined to make any official statements about that night.

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