Standard Sport understands the Gunners have made Gundogan a key summer target. The five-time Premier League winner will be out of contract at Manchester City this summer, so currently available on a free transfer.
City are keen to keep Gundogan around and remain in talks over an extension, while Barcelona are also keeping an eye on the situation as they plot their own bid. At the moment, nothing has been decided.
"There are talks, there are talks in the background," Gundogan said in April of possibly staying at City. "That's normal with a couple of months left.
"There's nothing decided yet, not from my side, not from the club's side - the talks, they continue. If there's a decision at one point then you guys [in the media] will be the first ones to know."
Gundogan, though, is hesitant over extending his City contract over fears he will not be able to cope with the stresses of playing for City, week in, week out, as their attack on four fronts: the Premier League football, Champions League and both domestic cups.
Speaking in April, after Guardiola said he wanted to keep Gundogan "forever", the midfielder said "my physical condition ... plays a part" in his decision to extend.
"I appreciate [Guardiola’s comments] a lot. We have won a lot together and to hear things like that of course brings me joy and a smile."