The 26-year-old defender joined the Bundesliga club in January, in search of regular football, after falling down the first-team pecking order at the Emirates Stadium.
Gunners boss Arsene Wenger allowed the Swiss international to leave initially on loan, but will probably be open to selling Djourou providing his £3million valuation is met.
With two years still remaining on his Arsenal contract, the Premier League club are in a strong position when it comes to negotiating with Hannover, who might struggle to meet Wenger's demands, if reports in the local German press are to be believed.
Djourou still hopes that an agreement between the two parties can be reached, allowing him to make the full-time switch to the AWD-Arena, where he is enjoying a return to form.
"It would be fantastic if the clubs could agree on a deal," he told Neue Presse Hannover on Tuesday.
"I have been granted the chance to play here and I am getting better and better and slowly finding my old form."