Reports earlier this week claimed Kahn was pondering a move away from Bayern Munich, with Manchester United thought to be hoping to take him to England.
Bayern Munich played down the rumours, but Kahn's father Rolf insists United are trying to bring him to Old Trafford.
"Oliver has had offers from Manchester United in the past, but the contact has certainly intensified over the past few weeks," Kahn told German daily AZ.
Bayern goalkeeping coach Sepp Maier revealed that Kahn was considering a move away to a new league after winning everything at the German giants.
"He's deadly serious," Maier told German daily Tz.
"He wants to move and the English league is calling him. He's already achieved everything with FC Bayern and that's why he's now looking for a new challenge."
United's reported interest in Kahn would be something of a surprise as they already have Tim Howard and Roy Carroll competing for the number one shirt and Sir Alex Ferguson is unlikely to want a sign someone coming to the end of their career as Kahn is.
