Katy Perry and Diplo's chemistry is reportedly "off the charts".

The 29-year-old singer and the 35-year-old DJ-and-producer have been linked for months, although it was recently claimed they had gone their separate ways. Earlier this month the pair put those rumours to bed with posts on social media, both adding pictures which seemingly showed they were on holiday together.

"They never split up, as they weren't really together. They've been carrying on their fling in secret for at least four months," an insider claimed to British magazine Heat. "He couldn't get on a plane fast enough when she called... she really likes him. The chemistry is off the charts."

The pair were thought to be enjoying some downtime in Jamaica. They posted separate photos of themselves in a hammock, and while none showed them together, eagle-eyed fans were quick to spot that the relaxing chairs in both images appeared to be the same. It seems Diplo wasn't too keen on the speculation though, as he quickly removed the shot from his Instagram page.

"Katy and Diplo totally had the best vacation ever. It was her idea to meet him in Jamaica for a quick break before she starts her US tour next week," the source explained.

Katy and Diplo were rumoured to have ended things in May, apparently after she got cold feet. The singer is divorced from British comedian Russell Brand and previously had an on/off relationship with John Mayer, so apparently didn't want anything too serious.

"She's doing OK and not too sad about it,” a source told In Touch Weekly at the time. “She wants to date and he wanted something much more serious. It was too much, too soon."