The 29-year-old Tunisia international has taken up a one-year option on his contract which was due to end this summer.

Manager Alex McLeish, who is looking to lead the club back into the Premier League following relegation on Sunday, said: "Mehdi has a good pedigree and is an international player.

"He is not afraid to take the ball and that's the type of player I'd like to have at Birmingham City.

"He's a great character and brings a good spirit to the dressing room.

"He trains the way he plays, he gives everything in training and everything on a matchday.

"Mehdi is the type of player that I identify with and want to bring into the club."

Young Birmingham players Jared Wilson and James McPike have both agreed new one-year contracts.

Nineteen-year-old full-back Wilson has made 10 reserve team appearances this season having come up through the youth ranks.

Striker McPike, also 19, has missed much of this season through injury.