The 19-year-old, who is regarded as one of the best young talents in European football, has been linked with a number of Champions League clubs this summer.
"We're planning with Julian. But what would I say if a €70m (£60m) offer came in? Everything else in this crazy football world is not for us to influence," he told reporters at a press conference.
Draxler scored 13 goals in 39 games for Schalke last season.