Demi Lovato urged Nick Jonas to dump Olivia Culpo.

Demi said: "He's a guy in his 20s and he's famous and he likes to have a lot of fun. Listen, even when he was in a relationship, I was like, 'Get out of that. You could f**k anybody that you want right now, so have fun and do that.' "

After splitting from Olivia, 23-year-old Nick spoke first to his father and brother Joe, then called Demi - who told him to go and be "free" and claimed she "didn't like" the model.

In a joint interview, Nick told Billboard magazine: "I internalise things, so we have this rule that we never want to hear about it in a tweet or something.

"She'd read me the riot act, so she's the third person I call -- my dad, Joe, then Demi. She was like, 'Just go, ¬create and be free.' She also said some other things..."

Demi laughed and added: "I go, 'Honestly, I didn't like her anyway.' It's not because she's mean or anything, but he has such a great sense of humour and I want him to be with someone that makes him laugh. I can tell if something's up because he'll close off."

Nick is finding being single "bizarre", but his 'Confident' singer pal - who recently split from Wilmer Valderrama after six years of dating - enjoys getting the "gossip" when he goes on a date.

Nick said: "I'm in a bizarre time in my life where I'm single, but that has been tricky. And she likes drama, so I'm able to talk about my dating s**t without feeling bad."

Demi added: "I'm like, 'Soooo, what's the ¬gossip? Who is it? Tell me everything!'... I give him a lot of advice. He doesn't always take it."

Before her relationship with Wilmer, Demi, 23, dated Joe Jonas and Nick admits he became an "emotional bridge" between his friend and his brother.

He said: "For a couple of years there was the Joe and Demi romantic thing, so I'd be this emotional bridge for them. But she and I were productive -- we'd write songs about it. We became even closer because it was never going to be [romantic]."