Chrissy Teigen and John Legend had a "major blowout" fight at Kim Kardashian and Kanye West's wedding.

The Hollywood couple watched as the reality TV star and rapper tied the knot at a star-studded ceremony held in Florence, Italy in May 2014, with John performing his hit song All of Me at the reception.

But during an appearance on Watch What Happens Live with Andy Cohen on Thursday night (18Jan19), Chrissy and John admitted that they did have a row during the day of the wedding.

“I don’t remember what it was about,” said John. "We try to think about this all the time. It was a major blowout to the point where every time I see them, I feel like apologising for it," the model added.

Host Andy then asked if they thought Kim and Kanye knew they were fighting.

"I don't think they knew," replied the 40-year-old singer.

While Chrissy, 33, went on to explain that the argument had stemmed from her feeling "intimidated" about the event.

"I think I was really intimidated. I think it came from a lot of insecurity and I took it out on John," she sighed. "(There) was a lot of fabulous, amazing people in one room. I think that's where it stemmed from. I was just very insecure. You know how things snowball into a bigger thing. And also drinking so that doesn't help."

Elsewhere in the interview, Andy also asked the pair what they about some of Kanye's controversial Twitter rants.

John stated that even though he often shakes his head over what the 41-year-old writes online, he can't deny that his pal "owns" his own opinions.

"I don't agree with a lot of the things he says. He owns it. He says what he's gonna say. And it's on him. It's weird because I get asked about it all the time, and I can't be accountable for what he's gonna say," he shared.