The Algeria international has been linked with a move to the north London side since Mahrez proved instrumental in the Foxes winning the Premier League title in 2015.
Mahrez scored 19 times and made 15 assists in their title-winning campaign, securing the PFA player of the year thanks to his eye-catching performances.
The African star was adjudged to have missed his chance to move to a big club after a disappointing 2016-17 season.
Mahrez has resdiscovered his best form this season following a return of six goals and five assists in 21 games in the Premier League.
Arsenal have been linked with a fresh move for Mahrez given the uncertainty surrounding contract rebels Alexis Sanchez and Mesut Ozil.
Sky Sports News reporter Dorsett warned Arsenal that Mahrez will cost £30m to sign in January or at the end of the current campaign.
“Mahrez wants to go. He has been performing pretty well,” Dowsett told Sky Sports News.
“It is whether teams are prepared to spend the money. Leicester won’t let him go cheap. They want around £30m for him. It’s whether one of the big boys is willing to spend the money.”
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