Emily Blunt, who's happily married to her husband John Krasinski, was previously in a relationship with jazz pop singer Michael Buble.

The two called it quits in 2008 amid rumors that he was cheating on her.

On Wednesday, when Howard Stern interviewed Blunt he mentioned that she and Buble were ''perfect'' together because they are both classy and elegant. Blunt let out a laugh and said she didn't know if she would call it that, but they "had a good time."

Stern then asked Blunt if Buble was ever unfaithful to her. "Well...," Blunt said as she trailed off with a sigh. "I don't know, it's complicated. I'm going red!"

Stern unperturbed asked her why she was going red.

"Because I never talk about it," the actress responded. "I never want to talk about it."

The Sicario actress did have kind words for her former flame, telling Stern that the pair "had a good time" and that she still loves his family.

"I never want to talk about it," she said of the relationship before eventually declaring: "I can't do it."

With regards to Buble, in another interview he has openly talked about his failed relationship in the past saying, "I was a jerk and I was careless and reckless with the hearts of women I was with."

The interview with Emily then got a little more awkward when the radio host asked the movie star if she's ever had a love scene with a co-star where he got aroused from it.

"Once," Blunt admitted. "I think it's just better to laugh about it."

"I think the reaction was, we were filming and they shouted, 'Cut,' and I went, 'Oop!' and he went, 'Oop! Sorry.' And that was it," she added. "We laughed about it because I don't want him to be embarrassed. I think that would be unfair if I was like, 'Oh my God!'"

Though she wouldn't name names, Blunt did say that her co-star wasn't famous.