London - Britain's finance ministry will hand the country's anti-fraud agency all the funds it needs to conduct a criminal investigation into alleged rigging of the $5.3trn-a-day currency market, a Treasury source said.
Finance minister George Osborne has written to the Serious Fraud Office (SFO) to say it will be given the financial support it needs for the investigation.
"I understand that the SFO is in the early stages of a major investigation into forex trading. Given the importance of this work, the Treasury will provide the required funding for this investigation," the source said the letter states.
The SFO opened a criminal investigation into allegations of fraudulent conduct in the foreign exchange market in July and said individuals could be charged next year. This is in addition to a regulatory clampdown which resulted in six major banks being fined a total of $4.3bn on Wednesday.
READ: Hefty fines for five major banks
The fines were for failing to stop traders from trying to manipulate the foreign exchange market, following a year-long global investigation.
The levies brought total penalties for manipulation of financial benchmarks to more than $10bn over two years.
Royal Bank of Scotland, HSBC, JP Morgan , Citigroup, Bank of America and UBS were hit with penalties. Barclays is still in talks with authorities over a settlement.
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