Don Cheadle is stepping in to replace Terrence Howard in Marvel Studios' Iron Man 2, says The Hollywood Reporter.

In the first film, Howard played Col. James 'Rhodey' Rhodes, Tony Stark/Iron Man's best friend and future armor-clad hero War Machine.

The trade says Marvel had no comment, but sources close to the deal said negotiations with Howard fell through over financial differences, among other reasons.

Marvel, which had wanted to work with Cheadle, then decided to take the role in another direction and approached the actor, who is shooting Antoine Fuqua's Brooklyn's Finest.

Justin Theroux is writing the screenplay for Iron Man 2, coming to theaters on May 7, 2010. Jon Favreau is returning as director, and Robert Downey Jr. is expected back as Stark/Iron Man. Gwyneth Paltrow also is expected to be back as Pepper Potts.