There's been a lot of speculation about whether fans would actually get to see 'Iron Man 4' hit the big screen, and Robert Downey Jr. has been nothing but vague in his answers. After recent statements from him jokingly saying he'd only do it if Mel Gibson came on to direct, the actor went on 'Ellen' with another non-answer.

"Will there be a fourth 'Iron Man'?" asked Ellen DeGeneres, to which RDJ replied, "I know there's going to be a bunch more Marvel movies, and they have big ideas on how to do it best, and we're in the middle of negotiation, blah, blah, blah." After one more prod from the host, he did say, "Okay, yes," though, given his delivery, it seems like he's not all that serious.

It's important to keep in mind that, during a Reddit AMA earlier today, he backtracked on his previous comments about doing 'Iron Man 4' with Mel Gibson. "It was an offhanded remark to a journalist and friend," he wrote. "I have other projects in mind for Mel and I - sooner than later the Marvel Roster will be made public and all questions will be answered."

So, that hardly seems like a confirmation of 'Iron Man 4.' Though, based on his statements to Ellen, he's "in negotiations" for some Marvel movie.

So far, Robert Downey Jr. is secured to appear as Tony Stark/Iron Man in 'The Avengers 2' (coming on May 1, 2015) and 'The Avengers 3,' and that's all we officially know. With rumors circulating that some of the Avengers team will be replaced with other Marvel heroes for 'The Avengers 3,' 'Iron Man 4' may not fit into the overarching plan moving forward. We'll only believe this when Marvel makes some sort of announcement.

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