De Niro beefs with Jay-Z

Hip-hop stars generally beef with other hip-hop stars, but it seems that Jay-Z has inadvertently angered Hollywood royalty.

According to a report in the New York Post, Robert De Niro exchanged cross words with the Brooklyn rapper over a series of unreturned phone calls.

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De Niro claims that Jay-Z failed to return a total of six phone calls after he promised to record a track for his Tribeca Film Festival.

The incident happened after the rapper approached De Niro at his table at a restaurant where he was celebrating Leonardo DiCaprio's birthday.

But he got short shrift from the 'Taxi Driver' star, who took him to task over the unreturned calls.

An insider speaking to the Post said that 'Bob wasn’t in any mood to make polite conversation. 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'.

The source added that he continued the tirade in front of the likes of Martin Scorsese and Cameron Diaz, who were also celebrating DiCaprio's birthday.

“De Niro kept telling him that he thinks he’s the man, but that he was disrespectful,” they said. “Beyoncé came over, but that didn’t calm Bob down.

“It was the talk of the party. Everyone was saying there’s only one star in New York bigger and badder than Jay-Z, and that’s Robert De Niro. He can be quite scary when he’s angry.”