The write off was significantly more than the 400 million Swiss franc Signa related loss analysts and a Swiss newspaper had estimated the bank would post from its ties to Rene Benko's Signa, which recently declared insolvency.

Rickenbacher, who has led the bank since 2019, will be replaced by his deputy, Nic Dreckmann.

"I deeply regret that the full loss allowance for the largest exposure in our private debt business has significantly impacted our net profit for 2023," Chairman Romeo Lacher said in a statement.

"We are refocusing our lending activity on more traditional areas, which are an important part of our wealth management offering."

($1 = 0.8634 Swiss francs)

(Reporting by Noele Illien, editing by Kirsti Knolle)