"We made him an offer, which he told us he didn't accept. He wants to leave the club at the end of the season," Kahn said in a press conference.
The towering 26-year-old will leave on a free transfer and has reportedly been linked to Chelsea, Newcastle and Barcelona.
Suele will be the third defender to leave Bayern in the last 12 months, after David Alaba's transfer to Real Madrid and Jerome Boateng's switch to Lyon.
Kahn was vague about whether Bayern will sign a new defender to replace Suele, "we have a lot of options when it comes to central defence".
However, senior club bosses reportedly met with the agent of Chelsea defender Andreas Christensen in December.