LONDON - British officials are considering the possibility of criminal prosecutions for a financial market manipulation scandal.

Barclays, which is among the banks being investigated, has been fined $453 million by U.S. and British agencies for providing false data on borrowing costs between 2005 and 2009.

The Serious Fraud Office said Monday that the issues are complex but it hopes to decide within a month on whether prosecutions are possible.

The Barclays chairman stepped down Monday about a week after the bank admitted manipulating the rate and agreed to the fine.

Chairman Marcus Agius -- who said “the buck stops with me" -- is the first to go in the scandal, which is expected to involve other more banks and is embarrassing British regulatory authorities.

Barclays has admitted that some of its traders attempted to manipulate the London Interbank Offered Rate, known as LIBOR, which is a calculation based on what large banks worldwide say it will cost them to raise money in the capital markets. Manipulation of the rate affects a wide range of U.S. financial products, including mortgages, credit cards and student loans.

Prime Minister David Cameron has called the scandal “extremely serious” and said management had “some big questions to answer.” Authorities also ordered a review into the working of LIBOR.

advertisement | advertise on newsday

Other banks being investigated include Citigroup, HSBC, UBS and the Royal Bank of Scotland.

“Barclays has become the poster child for this because they have been the first to be assessed by the regulators,” said Euan Stirling of Standard Life Investments, which holds some 2 percent in Barclays. “I think this is going to spread far and wide through the industry.”

In its agreement, Barclays admitted submitting artificially low estimates of its borrowing costs from late 2007 to May 2009 because it thought rivals were doing the same, and higher submissions would make it appear to be in trouble.

Barclays said it would launch an audit of its business practices, led by Michael Rake, its senior independent director, who will move up to deputy chairman.

The audit will undertake “a root and branch review of all of the past practices that have been revealed as flawed” and assess implications for its practices and culture. Diamond said its recommendations would be implemented in full.

Cambridge-educated Agius became chairman at the start of 2007 after more than 30 years as an investment banker and then chairman at Lazard. His wife Kate, a successful art dealer, comes from the Rothschild banking dynasty.

Wealth-X, the Singapore-headquartered research house which tracks the wealth of the world's richest people, estimates that Agius has a net worth of at least $35 million.