Machine Gun Kelly and Sydney Sweeney Have Never Hooked Up

Machine Gun Kelly and Sydney Sweeney have never been more than friends — despite the Internet buzzing with hookup rumors … TMZ has learned.

Sources with direct knowledge tell us the two have never hooked up … not once, not ever. The speculation got some fresh fuel Sunday when the rapper appeared on “Watch What Happens Live” and Andy Cohen tossed MGK a fan question asking if he and Sweeney were more than friends.

MGK’s reply? Peak MGK — “Shut up, dude” — sending the whole audience into hysterics. That was the last word on it … at least on TV.

But here’s why the question wasn’t totally out of left field. Back in May, just after Sydney’s split from fiancé Jonathan Davino went public, she was spotted partying with MGK in Vegas. Naturally, the rumor mill went into overdrive.

If you’re looking for hidden meaning, MGK never actually said “no” on the air — so people took his “shut up” as code for “we’re secretly dating” … or was it just him brushing off what he sees as a ridiculous idea?

Either way, our sources are crystal clear — they’re strictly platonic.