The popstar made the comments in a videotaped deposition on July 26, in support of her counterclaim against sacked Colorado radio DJ David Mueller, whom she alleges stuck his hand up her skirt at an event in June 2013.

Billboard reports the video was released on Friday, after a US District Court judge denied Swift's legal team's request to withhold all evidence in the case from the public.

"Right as the moment came for us to pose for the photo, he took his hand and put it up my dress and grabbed onto my ass cheek and no matter how much I scooted over it was still there," Swift says in the video.

"It was completely intentional, I've never been so sure of anything in my life."

In the videotaped deposition, the singer says she was left "completely stunned" by the event.

"I remember being frantic, distressed, feeling violated in a way I had never experienced before," she says. "A meet-and-greet is supposed to be a situation where you're thanking people for coming, you're supposed to be welcoming people into your home, which is the arena for that day, and for someone to violate that hospitality in that way, I was completely stunned."

Although Swift's request to withhold the deposition was denied, the judge did seal a picture of the incident, accepting her lawyers' reasoning that the photograph would only be used for "scandalous and prurient interests" if released to the public.

Swift is pursuing a counterclaim against Mueller, after he sued her claiming he was fired from his job and banned from Swift's concerts in September 2015, following an incident between the pair at Denver's Pepsi Centre more than two years prior.

In addition to his claim for lost income, Mueller is also bringing a claim against Swift for slander.

While Mueller's lawsuit does not deny someone placed their hand on Swift's behind while a picture was being taken at the event, he alleges he later spoke to an unnamed co-worker who "described and demonstrated how he had put his arms around [Swift], hands on her bottom" when it was his turn to meet the singer.

After the incident, Swift's team provided "evidence" to Denver's KYGO FM regarding the incident, and Mueller was fired in an "independent decision", People reports.

Swift counterclaimed a month later. "Ms Swift knows exactly who committed the assault – it was Mueller – and she is not confused in the slightest about whether her long-term business acquaintance, [KYGO FM programming director David Haskell], was the culprit," the countersuit states.

According to Billboard, Swift's team recently filed a motion for summary judgment, arguing their client's interference with Mueller's employment was unintentional, and that the statute of limitations had been exceeded for his slander claim.