The actor has been dating Rosie Coker for around two and a half years after meeting her on the set of one of the `Harry Potter` films, but her father has confirmed they have separated.
Malcolm Coker told website MailOnline: "Rosie`s not in this country at the moment. She`s trying to move on. She won`t want to talk about it."
He did not say when Rosie and Daniel had split, but they were believed to have been sharing his New York City apartment earlier this year.
It is now thought Daniel had been seeing another actress, Erin Darke, whom he met on the set of `Kill Your Darlings` - in which he portrays beat poet Allen Ginsberg - although they too are thought to have split, leaving her "devastated."
A source told Life & Style magazine: "Erin thought it was a real relationship, going as far as introducing Daniel as her boyfriend. He`s flown her out to London and taken her on dates and spent plenty of time with her in New York, but Daniel just up and left without a second thought. Erin was devastated." in August, Daniel - who is estimated to have a £50 million fortune - was also spotted with a mystery brunette in London.
The actor has previously talked about settling down with Rosie, saying earlier this year: "When growing up, I thought of marriage as being very official, drawing up a contract. It seemed slightly clinical to me. "But then you meet somebody that you really love and you think `actually, I wouldn`t mind standing up in front of my friends and family and telling them how much I love you and that I want to be with you forever`."