Matt Damon jokes about 'horrible' onscreen kiss with Scarlett Johansson after she ate an onion sandwich

Matt Damon is opening up about a less than ap-peel-ing onscreen kiss he once shared with Scarlett Johansson.

In a recent LadBible video, the actor and his Oppenheimer costar Emily Blunt weighed in on a variety of topics including whether or not it's okay to tell someone if they have bad breath. The pair strongly agreed you should, which ended up jogging Damon's memory about a particularly savory smooch he had with Johansson on the set of Cameron Crowe's 2011 film We Bought a Zoo.

"For me, it's less the costar that you're kissing, who you're probably going to be friends with anyway, and I can forgive some halitosis," Damon joked. "I had to kiss Scarlett Johansson — can you imagine how horrible that was for me?"

Twentieth Century Fox Film/Kobal/Shutterstock Scarlett Johansson and Matt Damon in 'We Bought a Zoo'

"Can you imagine how awful that was? It's such a shame she has such terrible lips and everything. It must have been so awful," Blunt teased, leading Damon to jokingly reply: "It was hell."

"What happened was we did a [scene] before lunch and it was like this nice little two shot that ended in the kiss and it was really good," he explained. "We went to lunch, and she and I both thought it was over, and she ate like an onion sandwich for lunch."

When they returned to set, the pair discovered that the kiss was, in fact, not over. "She came in and Cameron Crowe had set the camera up and it was like a tight shot of the kiss," Damon recalled. "And she goes 'Aw s---! I literally just had — I had like an onion sandwich. I thought we did the [scene].'"

Blunt then asked if Damon was at all "aroused" by their kiss, but he said that he was honestly too preoccupied to notice. "I was making fun of her the entire time about her onion breath, which I didn't even smell," he joked. "Her breath smells like roses."

Based on Benjamin Mee's 2008 memoir, We Bought a Zoo followed Damon's character, a recently widowed father of two, as he purchases and attempts to restore a run-down zoo with his family. Along the way, he falls in love with zookeeper Kelly Foster (Johansson). The film also featured performances from Maggie Elizabeth Jones, Thomas Haden Church, Patrick Fugit, Elle Fanning, and Colin Ford.

Watch Damon and Blunt discuss proper oral hygiene — and whether or not British or American food is the best — in the clip above.

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