Calvin Harris

The track is called Better Man but she won't be singing it herself - it's been penned for country band Little Big Town.

"But your jealousy, I can hear it now," go the lyrics, "you're talking down to me like I'll always be around".

"You push my love away like it's some kind of loaded gun" she also writes.

The band has confirmed in a Facebook Live Q&A that Taylor is behind the track.

"She sent us this song, and it was one that was really special to her," singer Karen Fairchild explained to fans.

The prolific DJ/producer talked to British GQ about his 15 month relationship and subsequent split with the pop star.

Harris told the publication "It's very difficult when something I consider so personal plays out very publicly."

Rumours had been circulating online that she was the lyricist behind This Is What You Came For, which features Rihanna.

Swift's representative confirmed it to People magazine, which the DJ retweeted from his official account.

He wrote: "Amazing lyric writer and she smashed it as usual."

The DJ and producer tweeted, "The only truth here is that a relationship came to an end & what remains is a huge amount of love and respect" after news broke recently that he and Swift were done.

Swift, who was with Harris for 15 months, retweeted him.

There has been much speculation about what happened with the pop power couple.

In the May issue of Vogue, Swift talked about her relationship with Harris, whose given name is Adam Wiles.

E! News learned Wednesday that the 26-year-old pop star and 32-year-old Scottish DJ and music producer, whose real name isAdam Wiles, split last week after dating for about 15 months and that he was the one who broke up with her. The two have not commented.

That's at least according to fresh reports that the Scottish DJ politely declined his label's idea for him to team up with his superstar girlfriend for his next single.

Harris's team are reportedly eager for him to get a big US female star on his next release, but he told them he didn't want to mix business and pleasure after the hassle caused by teaming up with ex-flame Rita Ora back in 2014.