The fine relates to four structured bonds sold by the bank between January and March with a 'medium-to-low' risk profile instead of 'high'. The bank offered to compensate those affected in July 2010.

The face value of the bonds affected was 16.5 million euros. The regulator started the investigation in 2011.

"Barclays has fully collaborated with the supervisory authorities and has been completely transparent throughout the process," a spokesman for the bank said, adding that it had put measures in place to make sure such an incident would never happen again.

Spanish banks have come under criticism for selling complex, high-risk products through their branches, like preferential shares.

(Writing By Sonya Dowsett; Editing by Helen Massy-Beresford)

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