Sinclair Broadcast Group Inc has approached rival U.S. broadcaster Tribune Media Co to discuss a potential combination, people familiar with the matter said on Wednesday, a deal that would hinge on existing regulations being relaxed. A deal between Sinclair and Tribune Media, which have market capitalizations of $3.8 billion and $3.3 billion respectively, would combine two of the largest U.S. local TV station owners and face regulatory curbs on how many households they can reach. REUTERS