Lisa Vanderpump has weighed in on the news of Tom Sandoval and Raquel Leviss's affair.

During an appearance on Watch What Happens Live with Andy Cohen on Wednesday, the TV personality addressed the bombshell news that Tom had cheated on his longtime girlfriend Ariana Madix with his Vanderpump Rules co-star Raquel.

Asked for her initial reaction, Lisa commented, "Gobsmacked. Flabbergasted. I mean, literally, no words. I didn't see it coming. Nobody saw it coming."

She went on to call the "Scandoval" very upsetting and noted that Ariana was "devastated" by the breakup.

"A lot of tears," she revealed. "Ariana was always that ride-or-die girlfriend. It seems like Raquel was the ride girlfriend and she was the die girlfriend - not good."

As for the apologies issued by Tom and Raquel, Lisa isn't convinced.

"Well, obviously, it was because he had some kind of reaction to the first apology, that he felt was necessary to apologise to Ariana. But I don't think these apologies are worth the paper or the social media they are written on. I really don't," the 62-year-old insisted. "I want to see true contrition. And I want to hope, that when the reunion comes, we actually all sit down, we can have a better understanding how this happened, why this happened, and when this happened."

Elsewhere, Lisa noted that she believed a report alleging castmember Scheana Shay punched Raquel after learning of the infidelity.

"Yeah, I think she did. I think she slapped (her) around the chops. But you know what, her feelings would be running really high. Because Ariana's been her best friend for like, 12 years. You forget, it's not just the show - they were together working four, five years before the show. I mean, they grew up together. So, she very much kind of has Ariana's back," she added.