Barclays, HSBC and RBS have set aside £237m, £400m and £500m respectively in anticipation of an investigation into the rigging of currency markets, it emerged on Friday. Six major banks are involved so far, including US institutions Citigroup and JP Morgan, and Swiss bank UBS, all of whom have also allocated funds awaiting hefty fines. The investigation is being carried out by the UK’s Financial Conduct Authority (FCA), and several US regulators.

In February, Martin Wheatley, Chief Executive of the FCA, warned that these accusations were “every bit as bad as they had been with Libor”, meaning the latest round of probes could reveal the biggest financial scam to date. The funds set aside so far surpass the penalties paid following the Libor scandal substantially – Barclays paid £59.5m in 2012, and RBS £87.5m in 2013.

[T]he latest round of probes could reveal the biggest financial scam to date

Barclays and HSBC, among other investment banks, have suspended their forex traders while the investigation is underway. Hopes are high for an industry-wide settlement which would prevent one bank being singled out and be overall less damaging to the reputations of individual institutions. Barclays executives in particular are likely to be crossing their fingers following the hit the bank’s reputation took after the Libor scandal, which lead to the dramatic resignation of its Chief Executive, Bob Diamond, in July 2012.

Perhaps the most eagerly anticipated aspect of the investigations is the expected release of emails and online chat messages between traders, which were allegedly used to discuss and plan the fixing of benchmark prices.

HSBC and RBS also announced that additional funds – £368m and £100m respectively – would be set aside to cover the cost of mis-sold payment protection insurance, in the largest and costliest mis-selling scandal of all time.