Marin said its U.S. arm Sovereign would have to adjust and improve some parts of its capital plan to resubmit to the Federal Reserve, but the changes would be qualitative rather than quantitative.

The U.S. central bank last week said Santander's plan for dealing with a stressed financial circumstances had "widespread and significant deficiencies" across its capital planning processes. Those included specific problems in governance, internal controls, risk management and its assumptions and analysis that support capital planning.

(Reporting by Jesus Aguado; Writing by Fiona Ortiz; Editing by Paul Day)