Gwyneth Paltrow reiterated multiple times that she had been the “victim” of a ski crash, as she began giving evidence in her US trial.

The Oscar-winning actress said she did “not believe” the testimony of previous witnesses and that her version of events was “categorically” the truth.

Ms Paltrow is being sued by retired optometrist Terry Sanderson over a collision at the Deer Valley resort in Utah in 2016.

She is accused of “slamming” into Mr Sanderson on a ski slope and falling on top of him, leaving him with several broken ribs and a severe concussion.

Ms Paltrow has denied the allegations, claiming that Mr Sanderson collided with her, and is counter-suing him.

The actress entered the witness box to give evidence wearing a dark blue skirt and a button-down blouse and began her evidence by describing herself as an “intermediate” skier who was “familiar” with the rules of skiing.

She denied that she had been engaging in “risky behaviour” on the day of the collision and reiterated multiple times that she had been skied into from behind by Mr Sanderson.

“I was confused at first and I didn’t know exactly what was happening,” she said, describing the incident.

“It’s a very strange thing to happen on a ski slope. I froze and I would say I got very upset a couple of seconds later.”

She added: “(I thought) Is this a practical joke? Is someone doing something perverted?… my mind was going very quickly and trying to ascertain what was happening.”

At one point during Ms Paltrow’s testimony, Kristin Van Orman, representing Mr Sanderson, attempted to recreate the sequence of events in the court room, with the actress giving her directions.

Mr Sanderson, who was also present, watched the recreation.

Ms Paltrow acknowledged that neither her ski instructor nor her children had seen the incident and did not remember fellow skier Craig Ramon being on the scene.

Mr Ramon previously gave evidence at the trial, in which he said he had witnessed the actress “slam” into Mr Sanderson.

“I did not believe his testimony,” Ms Paltrow said.

“I don’t believe he saw what he thinks he saw. He said he was 40 feet away and colour blind I don’t know how he can be positive with what he saw, especially with how much he changed his story.

“If you have two people in ski gear with helmets on and you’re 40 feet away I don’t know how you can discern who is who.”

She added: “What you have to remember is that when you’re a victim of a crash, your psychology is not necessarily thinking about the person who perpetrated it.”

“Mr Sanderson hit me and that is categorically the truth.”

The trial, in Park City, Utah, continues.