taylorcalvinlyricsgraziaImage credit: Getty Images

See how Katy Perry reacted to Calvin Harris’ tweets here. 

Calvin Harris has confirmed that Taylor Swift secretly wrote his hit song featuring Rihanna, This Is What You Came For.

A spokesperson for Swift confirmed a report by TMZ on Wednesday that Taylor wrote the song and sent a demo of it to Calvin, and the pair eventually recorded it in the studio together. The couple wanted to keep their collaboration a secret as to not overshadow the song, and so she was credited under the pseudonym Nils Sjoberg and it was decided Calvin should record it with Rihanna.

However, it’s understood that when Calvin was asked during an interview with Ryan Seacrest whether he and Taylor would ever work together and he replied “You know, we haven’t even spoken about it. I can’t see it happening though,” she felt disrespected and hurt, and their relationship soon soured.

Taking to Twitter on Thursday, Calvin confirmed the report and clarified he and Taylor’s contribution to This Is What You Came For.

“She sings on a little bit of [the song] too – Amazing lyric writer and she smashed it as usual,” he wrote.

“I wrote the music, produced the song, arranged it and cut the vocals though. And initially she wanted it kept secret, hence the pseudonym.

“Hurtful to me at this point that her and her team would go so far out of their way to try and make ME look bad at this stage though,” he added.

The Scottish DJ then appears to directly address his ex in the tweets – and even mentions her well-documented feud with Katy Perry.

“I figure if you’re happy in your new relationship you should focus on that instead of trying to tear your ex bf down for something to do.

“I know you’re off tour and you need someone new to try and bury like Katy ETC but I’m not that guy, sorry. I won’t allow it.”

“Please focus on the positive aspects of YOUR life because you’ve earned a great one.”

This Is What You Came For was released on the 29th of April and shot to the top of the charts around the world, debuting at number two on the UK Singles Chart, hitting number four on the US Billboard Hot 100 and reaching number one in Australia.