The Royal Bank of Scotland (RBS) is to challenge a court order requiring it to co-operate with an international criminal investigation into rate-fixing.
According to a report in the Telegraph, part-nationalised bank RBS - one of a number of banks under investigation for potentially fixing the LIBOR rate - is battling a court ruling to hand over confidential internal documents.
The documents could show its traders were also involved in the manipulation of the inter-bank lending rate, the Telegraph said.
The revelation comes just a week after Barclays' chief executive Bob Diamond was forced to resign over the scandal.
Barclays was fined £290m by UK and US regulators for manipulating the LIBOR rate in order to make extra profit.
Its shares have tumbled sharply following the scandal, while other banks including RBS, HSBC and overseas banks including Citigroup are also involved.
RBS has been resisting for more than a year investigators pursuing documents which allegedly detail wrongdoing by its staff.
A senior Canadian judge has ordered the bank, and several of its rivals to hand over evidence to investigators from the Canadian Competition Bureau, a law enforcement agency which protects the country's business and money markets from fraud.
The government has yet to step in, but considering it owns the vast majority of the bank's shares, it may yet have to intervene and force RBS' hand, despite its wish to remain effectively a silent partner.
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