Viacom Inc (VIAB.O) and Snapchat have extended a deal that will allow Viacom to sell advertising on the mobile app's behalf. Under the deal, Viacom will have the right to sell against its own content on Snapchat as well as Snapchat's U.S. owned and operated advertising inventory, a Snapchat spokesman told Reuters. That includes ads in Snapchat's un-partnered "Live Stories" which curate submitted posts from users in specific geographic locations or during large holidays, the spokesman added, but did not disclose the financial terms of the deal. Viacom is the only television company to have this arrangement with Snapchat, he said. The Wall Street Journal earlier reported that a deal was likely between the two. Viacom already had a deal with Snapchat that carries content for Viacom-owned networks Comedy Central and MTV. Snapchat is a mobile app where photos, videos and messages disappear in seconds, the Journal said. Viacom recently appointed Dauman as executive chairman, replacing majority owner Sumner Redstone, overriding calls for an independent board chief from Redstone's daughter, who voted against Dauman. The decision drew mixed reactions from investors.