Credit Suisse (CSGN.S) said on Monday that 61 billion Swiss francs ($68 billion) in assets left the bank in the first quarter and that outflows were continuing, underscoring the challenge faced by UBS Group (UBSG.S) in rescuing its rival.

Customer deposits declined by 67 billion francs in the quarter and the bank noted many matured time deposits had not been renewed.

"These outflows have moderated but have not yet reversed as of April 24, 2023," Credit Suisse said, adding that most of the money leaving the bank was from its wealth management division and occurred across all regions. The net asset outflow followed 110.5 billion francs pulled by clients from the bank in the fourth quarter.

The 167-year-old bank reported results for what is likely to be the last time, as its state-engineered marriage with UBS is expected to be completed soon. Much of Switzerland's reputation as a trusted global financial centre - particularly for the ultra wealthy - will rest on whether the two globally important systemic banks can be successfully integrated.

Shares in both UBS and Credit Suisse were up roughly 2% in morning trade, with some analysts noting the outflows were not as bad as feared.

But others said the magnitude was alarming.

Credit Suisse's ability to generate revenue appeared to be so damaged that "the deal could well remain a drag on UBS operating results unless a deeper restructuring plan is announced," London-based analyst Thomas Hallett at KBW said in a note to clients.

Assets managed by the flagship wealth management division plunged 29% to 502.5 billion francs at the end of March from the same period last year.

Clients rapidly started pulling money from scandal-plagued Credit Suisse after it was ensnared in market turmoil unleashed by the collapse of U.S. lenders Silicon Valley Bank and Signature Bank.

In the rescue package rushed together by Swiss authorities, UBS agreed to take over Credit Suisse for 3 billion francs in stock and assume up to 5 billion francs in losses. The deal also includes 200 billion francs in state financial guarantees.

Credit Suisse said that at the end of the first quarter, it had 108 billion Swiss francs of net borrowings from the central bank after paying back 60 billion. Since then, it has paid back another 10 billion.

The bank, however, reported a pre-tax profit of 12.8 billion francs, largely due to the controversial writedown to zero of AT1 bonds and a gain from the sale of a big portion of its Securitized Products Group to Apollo Global Management. When adjusted for these factors, it had a loss of 1.3 billion francs for the quarter.

The wealth management and investment banking units will continue to be loss-making in the second quarter, Credit Suisse said, adding that the group is also expected to post a loss this year.

UBS, which has flagged that it expects the deal to bring $8 billion in cost reductions by 2027, reports first-quarter earnings on Tuesday. On Monday, it said that Christian Bluhm - whose departure had been previously announced - will continue as its chief risk officer for the "foreseeable future" to work on the takeover.