AC Milan midfielder Sulley Muntari has been ruled out for up to six months following surgery on a ruptured anterior cruciate ligament.

The 27-year-old signed a permanent deal with the Rossoneri last month after a loan spell from city rivals Internazionale.

"Muntari underwent surgery for the reconstruction of the anterior cruciate ligament in his left knee," read a Milan statement.

"The recovery time is around five to six months, excluding complications."

Muntari has had previous spells with Udinese, Portsmouth and Sunderland.