The Sun reports that Robert ended the relationship, with a source telling the publication: "They were almost inseparable for their first two years together," before drifting apart recently.
"Rob is tired of it, has called off their engagement and told friends they have split. With so much history between them, though, there are still strong feelings there," the source continued. "It’s a difficult situation but things have become tough between them for some time and they both know they were no longer working as a couple."
Speculation over their split has grown since July, when Robert gave a bizarre radio interview claiming they were only "kind of" engaged.
Then, FKA Twigs stepped out at London Fashion Week in September without a band on her ring finger.
Sending love to Robert and FKA Twigs during this difficult time.
This article originally appeared on InStyle.