The bank has reported sharp outflows as wealthy clients move assets elsewhere, while the bank battles to recover from a string of scandals by focusing more on its flagship wealth management franchise and pruning back investment banking.

"Thankfully, the outflows have stabilized," Lehman told SRF in an interview to be broadcast on Monday.

Funds were also starting to return to the bank, he said, particularly in its Swiss home market.

Credit Suisse, whose shares recently plunged to a record lows, is in the midst of an overhaul which has included raising 4 billion Swiss francs ($4.23 billion) to bolster its finances.

"When you have a capital raising, which has a big dilution effect, that creates a lot of uncertainty and that leads to high volatility," Lehmann said in the interview.

"But I believe the situation has calmed. The business is definitely stable," he said.

Still, he expected 2023 and 2024 to be years of transformation for the bank as it seeks to stabilize after years of mishaps.

"It's true, the whole group will not be profitable next year," Lehmann said. "What is important is the progress we make.

"What is the earnings power of the Swiss business, wealth management, asset management and the part of the investment bank we retain, and then from 2024 produce positive numbers."