Sumner Redstone's National Amusements Inc on Thursday urged the boards of Viacom Inc and CBS Corp to explore a combination.
National Amusements owns 80 percent of the voting shares of both media companies, which separated from each other 10 years ago.
The optimal deal structure would be an all-stock transaction in which the stockholders of each company would receive shares in the combined company of the same class as they currently hold, National Amusements said in a letter to the companies' boards.
Reuters reported on Wednesday that National Amusements, owned by media baron Redstone and his daughter Shari Redstone, could contact CBS and Viacom as soon as this week to ask them to form independent board committees to discuss a potential merger.
(Reporting by Anya George Tharakan in Bengaluru; Editing by Ted Kerr)