The 24-year old Borussia Dortmund midfielder has reportedly spoken with United about a possible shift to Old Trafford at the end of the season but the Germany international has dismissed that as pure speculation.
"I think if they were true, I would know about it," he told SID.
Gundogan, who is under contract at Dortmund until the summer of 2016, is also a target for Arsenal, Chelsea, Bayern Munich and Barcelona but is remaining tight-lipped on where he could end up if he were to depart the Westfalenstadion.
"Barcelona are a great club, but there are many great clubs out there," he added.
"I cannot say anything right now. First and foremost the club has to suit me."