The 25-year-old has been heavily linked with a move away from Amsterdam, with Mikel Arteta's side believed to be leading the race for his signature.
According to Goal, the Gunners have been in talks with Onana's representatives for the past few months, but they have yet to decide whether they wish to step up their pursuit of the stopper.
Onana has been serving a year-long suspension from football, following a positive out-of-competition test for Furosemide.
However, after appealing UEFA's original punishment, the Cameroon international has had his ban reduced to nine months by the Court of Arbitration for Sport, meaning that he is available for first-team selection in November.
Onana will be allowed to leave Ajax before his contract expires in June 2022, and could be available for a little as £7m. body check tags ::