The Silent Witness actress and the TV chef are only said to have begun dating at the start of last month, but Fox has apparently decided to end their relationship.
An insider told The Mirror: "They're still friends, but there isn't any romance anymore."
Back in August the new couple were reported to have seemed very amorous as they ate at Carluccio's restaurant in Chiswick, West London.
An alleged onlooker said that they looked like "a pair of 18-year-olds" as they kissed and stroked each other's hands.
Before this brief romance with White, Fox dated peace campaigner Jeremy Gilley, with whom she has daughter Rose.