The 20-year-old was first troubled by an ankle problem while on international duty with England last summer and, apart from a pre-season appearance in the Emirates Cup, has not played a competitive match for the Gunners this season.
Wilshere, who needed surgery after initially wearing a protective boot, was set to return in early February, but felt pain when running in training last week.
An Arsenal statement read: "The Club can confirm Jack Wilshere has a small stress fracture to his right foot, however it is not accurate to state he has been ruled out for the remainder of the season.
"The injury is in a different area to his previous surgery, and it will be reassessed in around two weeks time by our medical team and medical experts who have worked together throughout Jack's recovery.
"This is a recognised complication of a complex rehabilitation process and, of critical importance, Jack's initial injury is recovering well."
The fitness of the combative midfielder will be of interest to England manager Fabio Capello as he prepares for his side's Euro 2012 campaign in Poland and Ukraine this summer.
Wilshere later tweeted: "I can confirm I have a stress fracture but it is not in the same area as my first injury which has healed very which I am happy about...
"I have developed a stress fracture in the Heal (heel) now and I don't want to put any time scale on it as I do not know how long it will take...
"I will update you more in a couple of weeks when I know more!"
