Following his split with Paradis last month, Depp has been romantically linked to Heard after starring alongside the blonde in flick, The Rum Diary.
Rumours of a romance between the pair were also fuelled after Heard split with her photographer girlfriend Tasya van Ree, who she started dating in 2008.
A source then seemed to confirm their relationship to Us Weekly, telling the publication that Johnny and Amber were "100% dating", adding: "He treats her really well."
An insider has since told Now magazine that Vanessa - who dated Depp for 14 years - is 'uncomfortable' that Heard could become close to her children with the actor, Lily-Rose and Jack.
They admitted to the publication: "Vanessa's devastated that Johnny's dumped her. She blames Amber and calls her a man-stealing, two-bit nobody and has vowed to not let her anywhere near their children."
The mag also reports that the French singer and Depp are due to come face-to-face in the near future to discuss details of their break-up.
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