The Nigeria international has made over 277 appearances for Chelsea since arriving at the club back in 2006 in a protracted transfer saga involving Norwegian side Lyn Oslo and Manchester United.
|4/5||Chelsea are 4/5 with Paddy Power to go trophyless next season
"We are interested in Mikel, and negotiations are under way," Aysal told Sabah.
Mikel is on an extended break after competing in the Confederations Cup but was non-committal when questioned about his Stamford Bridge future earlier on Tuesday.
Chelsea have also been linked with other midfielders that could replace the Nigerian at Stamford Bridge, with Roma midfielder Daniele de Rossi and Vitesse youngster Marco van Ginkel both on the west London club's radar.