“Fast & Furious 7” star Vin Diesel is reportedly being a jerk on the set of the upcoming film. According to a new report, the 46-year-old actor has apparently been so hard to work with that he is making the production move slowly.

The latest instalment of “The Fast and the Furious” film franchise has resumed production after months of hiatus to give time for the actors and the staff to grieve the death of Paul Walker, who died in November from a one-vehicle crash.

Walker had already filmed majority of his scenes, though he still had a few ones that need to be completed. That’s where his brothers, Cody and Caleb Walker, come in. They are currently sharing his role as Brian O’Conner.

But it’s not Walker’s death that has been stalling production; it’s Diesel’s attitude.

According to The Hollywood Reporter, Diesel has been so difficult on set that some staff have “fantasised about using the facial-replacement technology being deployed to put Walker in the film as a sub for Diesel as well.”

“Vin spent a whole day in his trailer one day,” a source said. “The next day, they waited four hours for him. He called a meeting [May 28] of studio execs to his trailer for two-and-a-half hours to say, ‘What the f*** am I doing here?’”

Another insider confirmed the report, claiming the crew are suffering from “low morale.”

Universal Pictures chairman Donna Langley has denied the report, saying, “This production is working through some challenges that are historically unprecedented. The crew and cast, led by Vin, have been nothing but terrific under these circumstances.”

Meanwhile, Walker’s character is reportedly being retired after the film, and will be replaced by another character.

“Paul’s character Brian O’Conner will be seen retiring, while his younger brother will join the crew,” a production insider told MailOnline.

“Of course, Cody isn’t a replacement for Paul in any way, but the producers were really grateful that he stepped in to help them finish this last film and Cody is so likeable and charming.

“It would be a tribute to Paul that Cody carries on the Walker name in the Fast and the Furious movies.”

“Fast & Furious 7” will be released in theatres on April 10, 2015.