Borussia Dortmund have warned Manchester United off their stars.

United manager Sir Alex Ferguson is chasing BVB trio Shinji Kagawa, Robert Lewandowski and Mats Hummels.

United would have to pay close on £50million for all three, but Dortmund managing director Hans-Joachim Watzke struck a defiant note by saying: "We expect Kagawa to go, but no amount of money will persuade us to sell the others."