Heat 2 is reportedly in trouble at Warner Bros.

According to Puck's Matthew Belloni, the upcoming sequel to director Michael Mann's 1995 action movie is facing a money crunch - with the filmmaker locking horns with Warner Bros. over its budget.

Mann's initial budget reportedly came in at over $200 million, though the director was said to have brought it down to $170 million.

Even so, that budget was reportedly still too high for the studio.

As a result, Warner Bros. is said to be exploring other avenues for making the movie, and is supposedly considering partnering with another studio or streamer on the project.

Heat 2 would be based on Mann's 2022 prequel novel of the same name, which follows master thief Chris Shiherlis (Val Kilmer) and detective Vincent Hanna (Al Pacino) across two timelines, exploring the events leading up to and following the explosive heist of the first film.

Belloni has also claimed that Leonardo DiCaprio has spoken with Mann about starring in Heat 2, which he has said may be the factor that pushes the movie across the line.

Heat followed criminal mastermind Neil McCauley (Robert De Niro) as he plans one last heist while being relentlessly pursued by dedicated LAPD Lieutenant Vincent Hanna (Pacino) - leading to a tense game of cat and mouse.

As their lives become increasingly intertwined, both men struggle with the personal costs of their relentless pursuits.

In March, Mann teased he had "handed in the first draft" of the script for Heat 2.

The 82-year-old director told Vulture: "I just finished the screenplay and handed in the first draft. 
In this case, it was Warner Bros. Any more than that, I can't talk about. But it's an exciting project."

Last November, Mann confirmed he was deep in the process of writing the screenplay, and hoped the project would move forward "as soon as possible" at Warner Bros.

Speaking with Collider, he said: "Nothing's definitely going because the sky may fall. But Heat 2 is at Warner Bros. I'm writing the screenplay for them, and hopefully, we will go forward as soon as possible."

The Collateral director also revealed he had been driving through Los Angeles in the early hours to spark ideas for the sequel.

He said: "I'm finishing the screenplay, and at 2:30 this morning, it woke me up in the middle of the night.

"So, I'm in the middle of writing the screenplay, and I wound up driving through LA at 3 a.m., which is fantastic, there are no cars, and ended up at [restaurant] Canter's Delicatessen because that's the only thing open 24 hours."

The filmmaker had also paid tribute to Kilmer - who died in April at the age of 65 from pneumonia following a battle with throat cancer - saying he was "tremendously sad" to learn the Heat actor had passed away.

He told The Hollywood Reporter: "While working with Val on Heat, I always marvelled at the range, the brilliant variability within the powerful current of Val's possessing and expressing character.

"After so many years of Val battling disease and maintaining his spirit, this is tremendously sad news."