Michael Bay will direct 'Transformers 4'.

Producer Lorenzo di Bonaventura has confirmed the filmmaker - who was at the help of the first three 'Transformers' movies in the series - will take charge of the blockbuster, which is set to be released in the summer of 2014.

He told MTV News: "Yeah Michael's gonna direct and it'll be releasing in the summer of 2014.

"We're excited and I think the challenge there is we really are gonna do a reboot, and what that's gonna be we don't even know yet."

But Lorenzo admitted there will be "a lot" of new cast members in the movie as no one from the previous three films has signed up yet.

He added: "It's a hybrid because there's still continuity going on, and there will be a lot of new cast.

"Whether there's anybody from the first cast, we don't even know yet. But it's going to be a whole new story."

Lead actor Shia LaBeouf could be unlikely to star in the fourth film in the franchise after previously distancing himself from reprising his role of Sam Witwicky.

He explained: "I just don't think right now there's anywhere to take Sam.

"If you'd asked me fifteen years ago if I would be here, I would've said, 'No way.' I don't have a grand plan. There's not this grand scheme. I just fall into movies. I'm blessed in that regard. The movies I've been involved in, it's never been plotted and planned and picked. I was 17 when I met Michael, and I'm sort of Michael Bay-raised.

"I've learned a great deal from Michael, as a person, as an actor, as a person on set. And it's not that I don't enjoy working with Michael. I love working with Michael. I would do any movie Michael wants to do. I just don't think there's anywhere to take it with Sam."