The 'How We Do(Party)' singer and her ex-boyfriend, Harris, broke-up after a year-long relationship and confirmed the split on twitter last week.
Ora has been enjoying the company of Sharieff, who was arrested with Bieber for drag racing earlier this year, reported Contactmusic.
"Rita was a little mortified that Calvin tweeted about the split but she is just getting on with things. She has been with Khalil but who knows how long it will last" a source said.
Harris, tweeted that the couple had separated their ways "some time ago" but wished her "all the best" in the future.
There was also a rumour that 20-year-old Bieber was the reason behind the split.