NEW YORK (Reuters) - Paramount Pictures is preparing for the possibility that director Steven Spielberg could leave the studio when his contract expires next year, calling the impact "immaterial," a top executive said on Tuesday.

In recent months, media reports have speculated that Oscar winner Spielberg, whose movies range from "Jaws" to the more recent "War of the Worlds," has been unhappy at Paramount after the company bought the DreamWorks movie studio that he co-founded in 1994 with David Geffen and Jeffrey Katzenberg.

Paramount, which is owned by Viacom Inc, agreed to acquire DreamWorks in 2005 for $1.6 billion amid much fanfare, and with the acquisition, Spielberg and Geffen agreed to stay on with Paramount through the end of 2008.

Katzenberg went on to be chief executive of publicly held DreamWorks Animation.

A departure is seen as hurting Paramount, whose recent blockbusters "Transformers" and "Blades of Glory" stemmed from DreamWorks. "Transformers," which Spielberg produced, has generated nearly $700 million at global box offices.

But Viacom Chief Executive Philippe Dauman told investors at Goldman Sachs' Communacopia media conference in New York that Paramount's diverse portfolio of new movies would minimize any potential damage.

"Steven and his team have the right to leave if they choose at the end of next year," Dauman said. "We're planning for that."

"The financial impact to Paramount first and especially to Viacom overall would be completely immaterial in the event somebody shows up to help them (Spielberg and Geffen) start a studio from scratch," Dauman added.

Viacom's current slate of expected releases include a mix of DreamWorks titles such as "Tropic Thunder" starring Ben Stiller and Jack Black, and a new movie that reunites "Titanic" cast members Leonardo DiCaprio and Kate Winslet.

Paramount is expected to release comic book-inspired "Iron Man" for Marvel and "Love Guru" starring comedian Mike Myers.