Barclays says its chief executive Bob Diamond has resigned with immediate effect, the latest scalp of a financial markets price-fixing scandal that’s also cost the job of the chairman.

Mr. Diamond said external pressures were damaging the bank.

The bank said Tuesday that chairman Marcus Agius, who submitted his own resignation a day earlier, would lead the search for Mr. Diamond’s replacement.

Barclays’ management has come under fire since the bank was fined $453 million last week by U.S. and British regulators for submitting false reports on interbank borrowing rates between 2005 and 2009. Much of that activity originated from traders in Barclays Capital, the division which Mr. Diamond headed at the time.

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