Lionsgate did not specify why it was asking for the publicity material to be pulled, but a source linked to the Italian distributors said they were in the process of removing "unauthorized" posters of the movie, tipped for glory in Hollywood's annual awards season.
The Italian posters feature large pictures of Hollywood A-lister Brad Pitt and Michael Fassbender, who have relatively small parts in the movie, but barely show black actor Chiwetel Ejifor, who plays the main role.
Many online commentators pointed out that the posters simply used Pitt's and Fassbender's huge celebrity to sell the film.
But others saw darker motives, and the film's makers responded apparently to limit any reputational damage.
"The '12 Years A Slave' theatrical posters featuring Brad Pitt and Michael Fassbender that were recently released in Italy were unauthorized and were not approved by any of the producers or licensors of the film," said Summit Entertainment, a Lionsgate subsidiary.
"Summit Entertainment, acting as exclusive sales agent for the licensors, is investigating and taking immediate action to stop the distribution of any unauthorized posters and to have those posters currently in the marketplace recalled," it added in a statement emailed to AFP by a Lionsgate spokesman.
The posters commissioned by Italian distributor BIM triggered a storm online, with some arguing they are racist in using photos of white stars to advertize a movie about a black character, who appears in almost every frame.
"REALLY? I don't remember Brad Pitt being the protagonist of the film or having such a pivotal role in the story to stay in the middle of the poster," said an Italy-based blogger on Tumblr called Carefree Black Girl.
"I sure don't know anything about marketing strategy to appeal audiences but isn't this going to far?" the blogger added.
Commenting on a Washington Post blog, Bfeely600 wrote: "I get that Brad Pitt is a recognizable star, yet I can't help but think once again that race plays a part."
On Twitter, actor-director David Eng wrote: "The folks who made the Italian 12 YEARS A SLAVE posters may not actually be racist.
"They just think all Italians are."
"12 Years a Slave" came equal first with crime caper "American Hustle" in nominations announced earlier this month for the Golden Globes, with seven nods apiece. It also topped nominees for the Screen Actors Guild (SAG) awards, and appears a likely frontrunner for the Oscars, which climax Hollywood's annual awards season on March 2nd.