JP Morgan Ashley Madison leak
Workers are reflected in the windows of the Canary Wharf offices of JP Morgan Reuters

The European Commission has slapped major banks JPMorgan, UBS and Credit Suisse with a €94m fine for their involvement in manipulating Swiss franc derivatives and Libor by taking part in cartels.

JPMorgan was the hardest hit banking major in the latest disciplinary action.

The Commission fined JPMorgan €61.7m ($78.8m, £48.8m) for rigging the Swiss franc Libor benchmark interest rate between March 2008 and July 2009. It was also fined €10.5m for participating in a cartel on Swiss franc interest rate derivatives.

Meanwhile, UBS was asked to pay a fine of €12.7m and Credit Suisse was fined €9.2m for joining the derivatives cartel. Royal Bank of Scotland escaped from a €115m fine as it alerted the Commission about the cartels.

"RBS condemn the behaviour by a small number of employees identified in today's announcement by the European Commission," said RBS in a statement.

"These offences were unacceptable and have no place in the RBS we are building. Once they were uncovered, management took swift action to notify our European competition regulator with the aim of quickly resolving this matter."

The banks prevented rivals from entering the interest rate derivatives market, as they colluded to fix a pricing element, which should have been decided by the market, according to the EU competition watchdog.

All the banks admitted wrongdoing in the case and received a 10% reduction in their fines.

"Acting against financial cartels is one of our top priorities, given the importance of a healthy, transparent, well-functioning financial sector for the entire economy," European Competition Commissioner Joaquin Almunia said.

A number of international banks were slapped with billions of euros in fines by global regulators for rigging benchmark rates and violating sanctions among other things.

In December, the European Commission slapped six financial institutions with a record €1.7bn fine for rigging two financial benchmarks.