The 23-year-old Germany international has been out of action for the past 14 months due to a back problem.
However, Gundogan has confirmed that he is available for Dortmund when they continue their Bundesliga campaign away to FC Koln on Saturday.
"I think that I am available for first-team selection again from here on," he told Sky Sports News. "The plan was to get in some training hours during the international break and make another step forward in a friendly game.
"I will be part of the squad again from the point that everybody returns from the international break. This weekend's match versus Koln should be that moment."
Dortmund are currently in 13th place in the Bundesliga table after taking just seven points from their opening seven matches of the season.