The 'Godfather II' actor Robert De Niro allegedly called out the rap mogul Jay-z in front of fellow A-listers, during Leonardo DiCaprio's 38th birthday party. A source told the 'New York Post' that Robert was upset that he called Jay-Z six times, but never got a call back. The two had a pending project together. Jay-Z agreed to record a song for the Tribeca Film Festival- but he never called back fellow Tribeca resident Robert with the details for the track. Robert said not calling back is "rude".