Kevin Costner has slammed a lawsuit launched against him as a "blatant lie".

After a stunt professional accused the Horizon: An American Saga - Chapter 2 director of breaching intimacy protocols, Costner filed a scathing response to her lawsuit this week.

In May, lead stunt double Devyn LaBella filed a breach of contract lawsuit against Costner, 70, alleging he had failed to provide a safe working environment and that she had been forced to perform a "violent" unscripted rape scene without the legally required notice or consent, and without a mandated intimacy coordinator present.

This week, Costner's legal team filed a response in the LA Superior Court refuting LaBella's claims.

"The story that LaBella tells, one of an insensitive director who forces a stunt person to endure a violent, simulated rape over and over again to obtain a gratuitous, unplanned shot, is a blatant lie," Costner's statement read.

The statement went on to argue LaBella had been asked to work on a shot that "did not involve violence, nudity or simulated sex".

In June, the film's intimacy coordinator, Celeste Chaney, submitted a statement supporting LaBella's allegations that she had been called to perform in an "unscheduled, unplanned violent rape scene" and that "she did not have the appropriate modesty garments to ensure adequate coverage, safety, or protection".