Several of the UK's biggest banks have been accused of processing hundreds of millions of pounds of dirty money from a Russian money-laundering scam believed to involve up to $80bn (£65bn).
HSBC, the Royal Bank of Scotland, Barclays and Coutts - which provides banking services to the Queen - are among those involved, according to The Guardian.
The Independent first reported on the scam in 2014, shortly after it was shut down by investigators in the former Soviet republic of Moldova.
The scheme, which ran from 2010 to 2014, allowed £15bn to be moved out of Russia. The latest documents suggest that figure may be as high as £65bn, according to The Guardian.
Much of the money is believed to be linked organised crime and corrupt officials, who were seeking to "clean" their cash so that it could be spent without suspicion.
The process involved using a series of front companies in the UK, which allow the actual owners behind them to remain a secret. The companies conducted fake business deals between themselves then sued each other in courts in Moldova, demanding the repayment of hundreds of millions of pounds of loans.
Vasile Sarco, an investigating officer in Moldova, told The Independent at the time of its original investigation: "This money was routed from Russia, but the companies incorporated in Britain were instrumental to transit the funds."
The new documents reportedly reveal that, once laundered, some of the money was spent on diamonds from a jewellers in Bond Street, furs, chandeliers from a Chelsea boutique and boarding fees at Millfield, a prestigious public school in Somerset.
Banking records detailing the scheme were obtained by the Organised Crime and Corruption Reporting Project (OCCRP) and Russian newspaper Novaya Gazeta.
The evidence includes details of 1,920 transactions totalling nearly £600m that went through UK banks, with a further 373 routed through US banks, according to The Guardian.
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All of the UK banks involved in the scheme said they have appropriate measures in place to prevent money laundering.
Shadow chancellor John McDonnell called for the scandal to be investigated by the National Crime Agency. "Britain cannot be a haven for the criminals of the world who are looking to hide their money."
He said it was, "deeply disappointing that there are British banks involved in yet another banking scandal as the actions of a few shouldn't overshadow the hard work of the thousands of employees in the sector who will have had nothing to do with this case.
“But it appears that some of these big banks haven't learnt the lessons of the past, and are clearly not doing enough to clamp down on financial crime and money laundering.”
A Barclays spokesperson said: “Barclays complies with the rules and regulations in all the jurisdictions in which it operates and has systems and controls in place to mitigate the risk of the bank being used to facilitate financial crime."
A spokesperson for HSBC issued a similar response: “The bank has systems and processes in place to identify suspicious activity and report it to the appropriate government authorities."
RBS, which owns Coutts, said: “We are committed to combating financial crime and money laundering in line with our regulations and have controls and safeguards in place to identify, assess, monitor and mitigate these risks.”
Additional reporting by PA
