Rita Ora "wishes the worst" for Calvin Harris and Taylor Swift.

Rita Ora

Rita Ora

The pair have sparked rumours they are dating after they were seen doing some shopping together and hanging out at a concert, which is something that has reportedly left the 'I Will Never Let You Down' hitmaker - who dated the DJ until last year - fuming.

A source told HollywoodLife.com: "She has bad blood with Calvin and he doesn't have any fondness for her either.

"Rita is glad that he is not her problem anymore and wishes them both the worst."

The 24-year-old singer is believed to have even gone as far as sending a warning about Calvin to the 'Shake It Off' hitmaker through a mutual friend.

Another insider added previously: "Rita has become concerned that Taylor is headed for yet another heartbreak. She passed a message to Taylor through a mutual friend to give her a head's up that while Calvin might be the most wonderful boyfriend at first, showering his partners with flowers, presents, and nonstop affection, he eventually turns as cold as ice for no reason.

"Rita knows Taylor has been through the ringer with so many high profile names and she just wants Taylor to be better informed about what she could be up for."