The singer, 22, and the model, 20, were often seen together but after a recent incident at a DKNY fashion event, Ora reportedly began to feel uncomfortable around her friend.
Delevigne grabbed Ora's microphone mid-performance and began to dance behind her.
“There’s a lot of hurt on both sides but Rita’s been working towards her singing career and carefully crafting her image for four years and it was all in danger of being a joke after that shabby performance,” a source said. "Rita's been advised to distance herself from the model."
The once- inseperable pair haven't been seen together since the party about a month ago.
The two once regularly referred to each other as "wifey" on Twitter and Instagram, but since the falling-out, Ora has declared designer Stella McCartney "my new wife."
For her part, Delevigne hired a yacht with Rihanna, with whom Ora does not get along, in Monte Carlo.