Taylor Swift's treatment of Calvin Harris "brutal", according to DJ's good friend John Newman

John told The Sun on Sunday newspaper: "From her side? Yeah, it did get brutal. I'm like Calvin, happy to take a back seat. I like my music to do the talking.

"When I tweeted that, there was a text almost immediately from Calvin. He was like, 'Down. Now'.

"And then it all came out anyway. No I'm not [friendly with Taylor any more], I don't agree with what's gone on?...?but I shouldn't comment further. I wouldn't know her well enough, weirdly. She's in another world."

Despite her split from Calvin, John admitted he remains a fan of Taylor's music and is sure her next album will be another success, regardless of whether she opens up about the relationship or not.

He said: "I really like her music so they'll be great songs either way. But I've had uncomplimentary things sung about me by exes. You get on with it."

Meanwhile, John also revealed he is poised to undergo an operation on a brain tumour, which has recently returned after he was initially diagnosed with the problem in 2012.

He shared: "As soon as my tumour came back I said, 'Right, I'm gonna blitz this out, get myself feeling incredible and get the strength of mind to deal with this'.

"If you go into an op like that feeling s**t because you're eating s**t food and you're fat and you're unhappy with your success and you're down about it, then it's gonna hit you like a ton of bricks.

"Calvin is my main inspiration in all of this. The way he got so healthy and inspired and focused, his friendship has been everything to me.

"I'm changing my lifestyle for ever. I want to come back with the best album I've ever made."