That certainly isn't the firm denial managers usually offer when their star players are linked elsewhere. If United's interest is genuine, then there looks like there could be a deal to be done.
However, as brilliant and world class as Kroos is, it's hard to see him being of much help to this current United team. His best position is in the attacking midfield slot behind the striker, and given that Juan Mata has just arrived, that's arguably the position on the field that David Moyes least needs to strengthen.
If we're going to poach a Bundesliga star, İlkay Gündoğan would be preferable. Pretty please?