BARCLAYS chief executive Bob Diamond is to give up his bonus this year after the bank agreed to pay out £290 million to settle an international regulatory investigation.

Mr Diamond, who was awarded £2.7m in 2011, and three senior executives agreed to waive their annual rewards as Barclays admitted its traders had manipulated interest rate setting over a four-year period.

It comes amid calls for Royal Bank of Scotland chief executive Stephen Hester to give up his bonus after thousands of the group's NatWest, RBS and Ulster Bank customers were hit by a computer glitch.

Mr Diamond's move came as Barclays was hit with the biggest ever fine imposed by the Financial Services Authority (FSA), of £59.5m, and fines of £128m by the US Commodity Futures Trading Commission and £102.6m by the US Department of Justice.

Barclays is the first bank to admit misconduct over the interbank lending rate, Libor, and its European equivalent, Euribor.

Libor reflects the rates banks demand for lending to one another, and is set daily by a panel of banks submitting to the British Bankers Association the rate they expect to pay.

It affects bank customers as it feeds through into the cost of loans and mortgages and the rates earned by savers.

Regulators found evidence of banks collaborating to exaggerate or depress Libor, to benefit their own positions. For instance, during the financial crisis, Barclays's Libor submissions were cut over senior management's concerns about negative media comment.

The FSA also ruled a significant number of profit-hungry derivates traders employed by the bank tried to cash in on Barclays' trading positions.

Mr Diamond said: "I am sorry 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 said the bank took action to fix the problems and co-operated with the authorities.

Some 20 banks are said to be under investigation by regulators from Europe, the US and Japan, which could mean Royal Bank of Scotland and Lloyds are embroiled in another scandal.

An RBS spokesman said: "The RBS Group continues to cooperate with the investigations and liaise with the regulators."

Lloyds Banking Group said: "As with many others in the sector, the group is assisting various regulators in their ongoing investigations into the setting of the London Interbank Offer Rate (LIBOR). Until these investigations are completed, it would be inappropriate for us to comment any further."

RBS has previously confirmed it has been accused of "manipulating US dollar Libor and price of US dollar Libor-based derivatives in various markets".

Lloyds and HSBC have also confirmed their activities as members of the Libor rate-setting panel were under investigation.

Meanwhile, House of Commons Treasury Committee chairman Andrew Tyrie has written to Mr Hester and the FSA's chairman Lord Turner to find out what went wrong with the RBS's computer systems.

He said: "It is unacceptable that so many people have suffered as a result of what looks to have been a major IT failure."

On Monday, LibDem peer Lord Oakeshott said Mr Hester should give up his bonus.