Royal Bank of Scotland said its finance director, Nathan Bostock, had resigned to join Spanish bank Santander after just 10 weeks in the job, dealing a major blow to the state-backed lender's turnaround efforts.
RBS said in a brief statement Bostock had on Tuesday evening told the board his intention to resign and would formally resign soon.
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The statement was rushed out after Sky News reported Bostock had quit to return to Santander UK, where he had previously held several positions, including chief financial officer.
Santander confirmed late on Wednesday that Bostock would be named chief risk officer and deputy CEO of its UK arm, which is due to be spun off and separately listed.