The 'Hot Right Now' singer has said that she was close to the reality star for sometime, but the relationship did not last as she was never there with him, reported Glamour magazine.
"I'm not going out with Rob. We were close for a while, but it didn't work because I was never there," Ora said.
"I was like a ghost. I used to get so frustrated with myself and then wonder why I was angry, so I decided it was best to keep [our relationship] friendly - especially at the moment, when there's so much going on," she added.
Kardashian is reported to have implied that the 22-year-old singer cheated on him, causing their split.
The 'Keeping Up with the Kardashians' star later attempted to clarify his tweets, saying that he had never even mentioned Ora's name in any messages about a recent break-up.