Kristen Stewart on wearing Princess Diana’s wedding dress

Kristen Stewart’s experience putting on a nearly identical replica of Princess Diana’s iconic wedding dress was not as exciting as one might hope.

“Putting that on was a spooky day,” the actress, 31, told “Entertainment Tonight” on the red carpet at the “Spencer” premiere this week.

Stewart, who portrays the late Princess Diana in the film, added that the wedding dress scene is embedded into a “montage” of several moments that flash before her eyes — including her wedding to Prince Charles in 1981.

“Even though I play her as a speculatively 29, 30-year-old person, we still wanted to give a taste of the scope of her life,” the actress shared. “Kind of touch on every part.”

Kristen Stewart filming A behind-the-scenes look at Kristen Stewart wearing the wedding dress replica while shooting the film.Frederic Batier

The actress portrays the late princess in the film, which is set over the course of a three-day holiday weekend in Dec. 1991. “Spencer” is based off of true events, including that the holiday weekend is when Lady Di decided it was time to end her marriage to Prince Charles.

Stewart has gained lots of Oscar buzz for her performance in the film, which The Post called “hauntingly brilliant.”

Kristen Stewart in a black bra top and long lace skirtKristen Stewart wore Chanel Haute Couture at the LA premiere of “Spencer.”Getty Images

During the interview, the “Twilight” actress also touched on a moment in the film in which we see Lady Di walk into a diner to ask for directions and immediately gets recognized by everyone inside — something she can actually relate to.

“It’s a little bit silly. There is an absurdist kind of nature to that scene because you’re like, ‘Dude, you are Princess Diana. You just walked into a fish and chips shop’,” she said during the interview. “Clearly you know people are going to have this reaction.”