REUTERS/Rafael Marchante
Bloomberg's John Glover and Joao Lima, citing Portuguese-language publication Expresso, said the bank is set to report a loss of €3 billion, or around $4 billion.
Rich Kleinbauer at RMK Research and Markets notes that this loss would be 15 times the company's original estimate.
Citing John Raymond, an analyst at CreditSights, Bloomberg said a loss of €3 billion would more than consume the €2.1 billion capital cushion the company holds.
Banco Espirito Santo is scheduled to report results for the first half of 2014 tomorrow after the market close.
In just the last month, shares of Banco Espirito Santo trading in Lisbon have fallen more than 40%.
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