"UBS is close to finalising a deal with UK, US and Swiss authorities in which the bank will pay close to $1.5 billion," the British financial daily reported, quoting unnamed sources familiar with the matter.
Around three dozen bankers and senior managers will be implicated, and according to the terms of the deal, the Swiss bank's Japanese subsidiary will plead guilty to a US criminal offence, the paper said.
Speculation has been rife in recent days over the amount of the expected deal, which will make UBS the second bank after Britain's Barclays to admit to wrongdoing.
If the Financial Times report is correct, the Swiss bank would be hit with one of the biggest fines ever imposed on a financial institution.
UBS was the first bank to reveal problems in the rate-setting process of the Libor, otherwise known as the London Interbank Offered Rate, used by banks to lend money to each other and which also affects a vast range of contracts around the world.
Other banks are also reportedly in advanced talks with regulators about settling allegations that they too manipulated their Libor information, including Royal Bank of Scotland and Deutsche Bank.
In June, Barclays was fined $452 million by British and US regulators for attempted manipulation of interbank rates between 2005 and 2009.
The Libor system was found to be open to abuse, with some traders lying about market interest rates to boost positions or make groups seem more secure.