Cape Town - Calvin Harris lashed out towards Taylor Swift on Twitter on Wednesday after it emerged that the Shake It Off hitmaker co-wrote his song This Is What You Came For.
The Scottish DJ first complimented his former flame on her incredible ability to pen smash hits after it was revealed she'd sat down and written the lyrics before sharing it with him while they were dating.
But he soon changed his tune towards her and even brought Katy Perry into the mix.
See the Twitter rant here:Taylor's representative confirmed she'd written the song under the fictional name Nils Sjoberg.
He told the MailOnline: "Taylor Swift wrote This Is What You Came For under the pseudonym Nils Sjoberg."
The Blank Space singer ended her relationship with the hunk early last month and the "breaking point" in their 15-month romance reportedly came after he was "disrespectful" by saying he'd never work with her while promoting the track.
The pair were keen to release the song together but feared their relationship would overshadow the song, so Calvin brought in Rihanna to record the vocals.