Banking giant Barclays is to pay penalties of £290m to settle claims that it manipulated the interbank lending rate.
The bank was fined £59.5m – the largest imposed by City watchdog the FSA – and also agreed payments to authorities in the US.
Chief executive Bob Diamond apologised for the incident and said he and fellow executives Chris Lucas, Jerry del Missier and Rich Ricci have agreed not to take a bonus this year.
The London inter-bank offered rate (Libor) and its equivalent in Europe, Euribor, reflect the rates that banks demand to lend to one another overnight.
The FSA said that during the financial crisis Libor submissions were reduced due to senior management’s concerns about negative media comment.
The regulator added that submissions on Libor and Euribor took into account requests from interest rate derivatives traders, who were motivated by profit and sought to benefit from Barclays’ trading positions.
The breaches involved a significant number of employees and occurred over a number of years, the FSA added.
Mr Diamond said: “I am sorry that some people acted in a manner not consistent with our culture and values.
“The events which gave rise to today’s resolutions relate to past actions which fell well short of the standards to which Barclays aspires in the conduct of its business.”
Mr Diamond took a £2.7m cash bonus last year despite widespread criticism that his pay failed to reflect the struggling performance of the bank.
Tracey McDermott, the FSA’s acting director of enforcement and financial crime, said: “Barclays’ misconduct was serious, widespread and extended over a number of years.”
In the US, the Commodity Futures Trading Commission brought attempted manipulation and false reporting charges, leading Barclays to agree to settle a penalty of $200m (£128.2m).
In addition, as part of an agreement with the US Department of Justice, Barclays admitted to its misconduct and agreed to pay a penalty of $160m (£102.5m).