(Reuters) - Viacom Inc <VIAB.O> said on Monday it named Bob Bakish, a 19-year company veteran, as acting chief executive, replacing Tom Dooley.

Viacom had said last month that Dooley was leaving the company on Nov. 15.

Bakish, who most recently headed the company's international media networks, was also named president and CEO of Viacom Global Entertainment Group.

The new unit combines the international media networks with Viacom's music and entertainment group.

The appointment comes as Viacom, which owns Nickelodeon and MTV, hired financial advisers earlier this month to explore a merger with CBS Corp <CBS.N> following a proposal by Sumner Redstone's National Amusements Inc, a majority shareholder of both companies.

"We are determined to move forward aggressively to strengthen Viacom for the future, whether as a stand-alone company or in a potential combination with CBS," Chairman Tom May said in a statement.

There has been increasing speculation among media industry insiders that CBS and Viacom may recombine, with CBS CEO Leslie Moonves at the helm, after Redstone and his daughter, Shari Redstone, won the battle for control of Viacom, resulting in the departure of Viacom's former CEO Philippe Dauman in August.

Bloomberg had first reported the news on Wednesday.

(Reporting by Anya George Tharakan in Bengaluru; Editing by Anil D'Silva)