The Germany international, who is ruled out of Euro 2016 due to a knee injury, becomes new City boss Pep Guardiola's first signing since taking over from Manuel Pellegrini
The 25-year-old confirmed the news in a video posted on City's official Twitter feed.
He said: "Hello City fans
You have been tweeting me for a long time and now I officially announce that I am a Manchester City player
Hope to see you soon."
Source : PA
Source: PA