Pressure was mounting on Credit Suisse today over losses linked to the downfall of Archegos Capital.
Analysts have warned that the bank's dividend and share buyback plans may need to go on hold and investors advised to vote against management pay.
Losses at Archegos, a family office run by former Tiger Asia manager Bill Hwang, sparked a sell-off in bank stocks yesterday.
Investors feared they would be forced to take big write-downs after extending billions of dollars in leverage to the fund.
Global lenders may lose more than $6 billion on Archegos, sources familiar with trades involving the US investment firm have said.
Credit Suisse and Japan's Nomura are set to bear the brunt of this, according to statements from the banks and sources, with one source close to the Swiss lender saying its losses could be as high as $4 billion.
The bank has declined to comment on the size of losses.
Credit Suisse's shares fell further today, taking their loss so far this week to almost 16%. Shares in most other major European banks were up in morning trade.
The brokerage arm of Japan's Mitsubishi UFJ Financial Group today flagged potential losses at its European subsidiary of around $300m related to a US client.
It declined to comment on whether that client was Archegos.
The prospect of big losses at Credit Suisse is piling pressure on the lender's management, already reeling from the fallout surrounding collapsed supply chain finance company Greensill.
Earlier this month Credit Suisse shut $10 billion of supply chain finance funds that held bonds issued by Greensill, and is overhauling its asset management business to deal with the scandal.
Ethos, which advises shareholders on corporate governance, said Credit Suisse investors should vote against board and executive pay at its upcoming annual meeting.
"These new cases add up to an incredible number of governance failures," Ethos Foundation Chief Executive Vincent Kaufmann said.
Several analysts also flagged today that Credit Suisse's share buyback programme and dividend may be at risk as a result of the scandal.
"The hits just keep coming for Credit Suisse," wrote Eoin Mullany at Berenberg.
"We believe Credit Suisse will need to suspend its share buyback while in the longer term we believe it will lead to it reassessing the way it takes and manages risk," he added.
Analysts at Citi said they estimated the bank's pretax losses at around $3.5 billion.
Credit Suisse declined to comment on its buyback plan or dividend policy.
The bank had planned to buy back at least 1 billion Swiss francs ($1.06 billion) worth of stock this year.
Its regulator has already told it to hold more capital due to the Greensill fallout, which the bank said at the time would not affect its buyback plans.
Other major banks have so far not said they expect a major impact from the downfall of Archegos, with Deutsche Bank saying it had not incurred losses after "de-risking" its Archegos exposure.
Goldman and Morgan Stanley were quick to offload shares on Friday, averting a material financial impact, sources familiar with their trades have said.
Archegos's problems started last week when a disappointing stock sale by media giant ViacomCBS triggered devastating bank margin calls for the fund, three sources familiar with the matter said.
Shares in ViacomCBS fell 23% last Wednesday after the media company sold shares at a price which diluted its value.
Regulators in the US, UK, Switzerland and Japan have all said they are closely monitoring developments.
