Harry Styles and Nadine Leopold haven't officially addressed the relationship rumors, but according to Heat magazine, they were caught showing major PDA at his birthday bash! Even in a room full of people, they were "kissing and holding hands."

CLICK HERE FOR PICS FROM HARRY’S 21ST BIRTHDAY!

Since we have no pictures of them together from the event, we don't know for sure if this report is true or not. But we've already caught them going on multiple frozen yogurt dates and special birthday dinners, so it's not like they're hiding how much they like each other.

Maybe the One Direction singer is waiting to make things official? He's currently on tour, so their long-distance situation might be hard. It sounds like things are getting serious — we've heard that he's falling in love with the model — but they still haven't publicly confirmed that they're a couple. Leave it to Harry to keep us guessing!

Do you think that Harry and Nadine are serious? Do you think they'll go public with their relationship? Sound off in the comments!

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