"There are a lot of restructuring charges attached to what we are doing. It's a big clean-up, but it's necessary," he said.
As part of the earnings release, Credit Suisse announced that it was accelerate its program of cuts across the bank, including approximately 4,000 jobs.
The challenge for the group lies in Credit Suisse's equities and fixed income business, according to the CEO. "The fixed income activity has suffered," he said. The cost of withdrawing from certain activities in investment banking, as flagged last year, also took its toll.
"It's important to be in investment banking," Thiam said, but denied rumors he was talking to Wells Fargo about a sale of part of the investment banking and capital markets business.
The wealth management business was however performing well. While rival UBS saw outflows of 3.4 billion Swiss francs in the fourth quarter, Credit Suisse recorded 4.4 billion Swiss francs in net new assets.
Thiam said he believed the group's faith in emerging markets and Asia and had helped attract clients. Many billionaire clients were looking for opportunities and had the means to withstand volatility. "A lot of things are mispriced...and mispricing by definition creates opportunity."
"Towards the lower end there is a drop in activity...but in terms of collecting the assets and getting people to come in, we are not yet finding that difficult."
Thiam, brought in as chief executive in July from insurer Prudential, warned in a statement that the environment had "clearly" deteriorated materially during the fourth quarter of 2015. The bank's exposure to the energy sector, a potential concern amid plummeting oil prices, was "manageable", he told CNBC. It played a role in the fourth quarter losses, but not a major role, Thiam said.A combination of uncertainties surrounding Chinese growth, the abrupt drop in oil prices, large industry mutual fund redemptions of financial assets, asynchronous policies by leading central banks, lower liquidity, a strong Swiss franc had made the fourth quarter of 2015 challenging, he said. The group had seen lower levels of client activity.
"It is not clear when some of the current negative trends and in financial markets and in the world economy may start to abate," he said.
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