The 26-year-old’s BVB contract runs until 2017, but he has long been courted by the Red Devils, whose manager Louis van Gaal is looking for a defensive leader.
The Germany centre-back told Monday’s edition of Kicker that he “often thinks about moving abroad”, but gave Tuesday’s instalment of Bild a far stronger indication of his Manchester thoughts.
“If I was to transfer abroad at some stage, then it would only be to Manchester United,” Hummels said.
Hummels’ agent, his father Hermann, is a friend of Van Gaal from when they both worked at Bayern Munich, where Hummels senior was youth team co-ordinator until 2012, while Van Gaal was head coach from 2009 until 2011.
Dortmund CEO Hans-Joachim Watzke revealed the club captain informed them he is weighing up his options.
“Mats had a conversation with [director of sport] Michael Zorc and myself two weeks ago, when he informed us that he is thinking about his future,” said Watzke. “That is completely legitimate. He has a contract until 2017 and we haven’t received an offer, therefore we’re pretty relaxed.”