Michael Bay has regrets.

Speaking with Unilad, the “Ambulance” director revealed that none other than Steven Spielberg warned him against making too many “Transformers” movies.

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“I made too many of them. Steven Spielberg said, ‘Just stop at three’. And I said I’d stop.

“The studio begged me to do a fourth, and then that made a billion, too. And then I said I’m gonna stop here. And they begged me again. I should have stopped. They were fun to do.”

In total, Bay made five “Transformers” films. The 2018 prequel “Bumblebee” was helmed by Travis Knight, while the upcoming “Rise of the Beasts” will be directed by Steven Caple Jr.

Spielberg was a producer on the first “Transformers” film, starring Shia LaBeouf, and has executive producer credits on subsequent franchise entries.

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Despite the admission, Bay maintains that he still gave each film everything he had.

“I’m passionate about any movie I do, from ‘Pain & Gain’ to ’13 Hours’. I like going from big to small, you want to move off the same thing.”

Talking about his new film “Ambulance”, Bay said, “It was cool to do this, a kind of grittier, tougher action movie, a little more hardcore. I got some great performances. I’m excited.”