UBS Faces $1bn Fine Over Libor Manipulation
UBS is expected to be hit with a fine of around $1bn to settle Libor manipulation charges.
The total amount - worth around £620m - will be a combined penalty from US and UK regulators, and is expected to be confirmed early next week.
UBS declined to comment on the news.
It comes two days after the Serious Fraud Office made three arrests as part of its investigation into the fixing of the interbank lending rate.
Sky sources suggested that one of the people detained previously worked as a trader at UBS, which has a big presence in the City of London.
Last month, the Financial Services Authority fined the Swiss bank £29.7m for internal failings that allowed a London-based rogue trader to cause the biggest fraud in British history.
Unauthorised trading by Kweku Adoboli resulted in £1.4bn worth of losses for UBS.
To date, Barclays is the only UK bank to have been fined in connection with the rigging of Libor.
It was fined £290m in June, and its chief executive, Bob Diamond, resigned the following month.
Libor - or the London Interbank Offered Rate - is the rate used to fix the cost of borrowing on mortgages, loans and derivatives.