America's Got Talent judges Howie Mandel, Mel B, Heidi Klum and Simon Cowell. Picture: Heidi Klum/Instagram

Simon Cowell thinks Mel B took his joke about her wedding night too seriously after she soaked him on stage during 'America's Got Talent'.

The 42-year-old singer threw a glass of water over her 'America's Got Talent' co-judge and stormed off the set of the live show last week after he made the jibe, and while they "over it", the 57-year-old music mogul thinks she lacked a sense of humour.

WATCH: Mel B storms off AGT after Cowell row

Speaking to Terri Seymour on 'Extra', Simon said: "I was trying to make light of something ... I thought she'd have a sense of humour. She lost it.

"I was the one who got soaked I should be mad at her. She's fine. I'm fine. Just one of those things. Terri, we got over it."

However, Mel - who split from husband Stephen Belafonte in March amid accusations he had been abusive and got their nanny pregnant - says she reacted the way she did because she was already upset after watching an an act audition which reminded her about her father who recently died of cancer.

She said: "The act before mad me cry, because it's all about dads and cancer and I just lost my dad.

"He goes and says something stupid like that, so then I got angry.

"How do you know what my wedding night was like all those years ago?"

The former Spice Girl previously quashed speculation her tantrum was staged for the camera.

She insisted: "My journey tonight was all over the place. But I'm a very real, honest person, so what you see is what you get."

Simon had made the insult after magician Demian Aditya saw his trick flop due to a technical malfunction. 

He quipped: "I kind of imagine this would be like Mel B's wedding night. A lot of anticipation, not much promise or delivery."

Fellow judge Heidi Klum previously admitted she thought Simon "deserved" his soaking.

She said: "I mean, you know, [Simon] was pretty harsh today. So he deserves getting wet from her. I knew it was coming too. She's not going to take that from him.

"I just have to be quick, always. When I feel it coming, I don't know. Am I going backwards, am I going forward? You have to be quick with those two."