NEW YORK (CNN/Money) - An advocacy group Friday accused sandwich chain Subway Restaurants of being "anti-American" because the tray liners that the company is currently using in Germany display an obese Statute of Liberty and a German word that it claims is a pejorative term for Americans.

The Washington, D.C.-based Center for Individual Freedom said it took issue with the tray liners that show an overweight Statue of Liberty holding a burger and fries in her hands along with the headline "Why are Americans so fat?"

According to the group, the tray liners promote Morgan Spurlock's controversial documentary "Super Size Me," in which Spurlock, who directed and starred in the film, gained weight by embarking on a 30-day experimental diet that consisted exclusively of McDonald's (MCD: Research, Estimates) food.

The group also alleged that the ad promoting the movie contains a German word "amis" that is a derogatory term for Americans.

"It is appalling that Subway, a U.S. company, would attack Americans and the Statue of Liberty, our most recognizable symbol of freedom, in a time of war just to gain market share," the Center's executive director, Jeffrey Mazzella, said in a statement.

"Subway's advertising strategy amounts to nothing more than a shameless and irresponsible marketing scheme," he added. "The company is exploiting cultural tensions and inflaming anti-American sentiment abroad just to sell more sandwiches.

Subway's president and founder Fred DeLuca denied the group's allegations.

"The tray liners, which appeared only in our franchises in Germany, contained a movie promotion in German for "Super Size Me" that was put together by the German distributors of the movie. They have not have been as sensitive to certain aspects of the ad as others," DeLuca told CNN/Money.

"In terms of being anti-American, that's wrong," he added. "Our German franchisees are about the most pro-American people you can find. They found an American product, liked it and brought it back to their country."

DeLuca also said that it was his understanding that the word "amis" wasn't pejorative, but rather a shortened German word for "American."

"It's similar to the use of 'Brit' for 'British,' " he said. DeLuca said the tray liner ad was a limited promotion for the movie.