The France youth international spent time in north London on trial earlier this summer, much to the dismay of the club, which later rejected an initial offer from the Gunners for the 17-year-old.
And Fortin has now stated that Arsenal are just one of a number of clubs interested in Niang's services, and said that he expects the issue to be resolved by the time the Premier League season kicks off.
"Arsenal made me a propostition," he revealed to L'Equipe. "Other clubs are interested: two in England and one in Italy. I think there will be an issue here for a fortnight."
Niang made his first-team debut for Caen in 2011, but was unable to save the club from relegation last season. He has also made two appearances for France at Under-21 level.
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