NEW YORK (Reuters) - Amazon.com has halted pre-orders of some Disney movies, the Wall Street Journal reported on Sunday, in what appears to be another contract dispute after the online giant began a protracted spat with publisher Hachette Book Group this year.

Physical copies of titles such as "Maleficent" and "Captain America: The Winter Soldier" were unavailable for order on Amazon.com on Sunday. Digital copies of some of the movies in question were still available for pre-order.

Amazon.com did not immediately respond to a request for comment on the report. A Disney spokesman had no comment.

Amazon has been waging a battle against Hachette, the fourth-largest U.S. book publisher, over the price the online retailer can charge for e-books. Hachette is owned by France's Lagardere.

A group called Authors United ran a two-page ad in the New York Times on Sunday, criticizing Amazon for halting pre-orders from some Hachette authors and slowing delivery of books by Hachette authors. The ad was signed by more than 900 writers, including Stephen King and Donna Tartt.

Amazon says pricing e-books at $14.99 or $19.99 is too expensive. It argues that cheaper e-books sell more copies and so ultimately generate more revenue and more royalties for authors.