An investigation by the European Commission found that foreign exchange traders from a ‘cartel’ of five banks, including RBS, colluded on trading strategies between 2007 and 2011.
The report said traders “exchanged sensitive information and trading plans” with one another on internet chatrooms, while they occasionally “coordinated their trading strategies” as well.
UBS was also part of the cartel, the Commission said, but it escaped punishment because it reported the wrongdoings.
“These cartel decisions send a clear message that the Commission will not tolerate collusive behaviour in any sector of the financial markets,” said commissioner for competition Margrethe Vestager.
“The behaviour of these banks undermined the integrity of the sector at the expense of the European economy and consumers.”
RBS shares edged 0.3% higher to 230.8p on Thursday, while Barclays was broadly flat at 160.0p.