Barclays chief executive officer Bob Diamond Tuesday quit his post over the London Inter Bank Offered Rate (LIBOR) fixing scandal, in which the bank was fined £290 million ($450m) by the U.S. and UK regulators last week.

The resignation came a day after its chairman Marcus Agius announced his decision to quit his post and the bank announced that it would go for a root and branch review of its past wrong practices and also to make the auditors' findings public.

There was immense pressure on Diamond to resign over the scam in which the bank had admitted to attempting to manipulate the key interest rate.

The buck in Barclays stops with Bob Diamond, and it is Bob Diamond who must accept responsibility, John Mann, a Labor politician who is part of a panel of lawmakers said Monday, Reuters reported. Shareholders also had demanded Diamond's resignation.

No decision over that period was as hard as the one that I make now to stand down as chief executive. The external pressure placed on Barclays has reached a level that risks damaging the franchise - I cannot let that happen, Diamond said in his statement announcing his resignation.

I look forward to fulfilling my obligation to contribute to the Treasury Committee's enquiries related to the settlements that Barclays announced last week without my leadership in question, he added. Diamond will appear before the Treasury committee Wednesday.

Agius will continue as chairman of Barclays until a replacement is found for the posts of CEO and chairman.

Many other banks, including Citygroup, HSBC and UBS, are also being investigated by the North American and European authorities, and analysts expect a few more cases of malpractice to be unearthed in the probe.

Libor Scandal

Libor (London Inter Bank Offered Rate) is the average rate in which London banks lend money to one another and is the benchmark for setting prices on derivatives and other financial products like the euro bonds to the tune of $350 trillion.

Barclays was fined for submitting artificially low Libor estimates for its borrowings in the period 2007-2009. The bank also agreed that some of its traders had attempted to manipulate the setting of Libor rates.

Submitting lower than actual rates would indicate that Barclays is a better lending risk than actually it was, BBC reported.

Richard Hunter, Head of Equities at Hargreaves Lansdown Stockbrokers, commented: The revolving doors at Barclays are working overtime. In an extraordinary volte-face, the chairman's resignation has been withdrawn at the expense of the Chief Executive and the apparent indecision has hit the shares again in early trade.