British citizen Tom Hayes has been charged with eight counts of conspiracy to defraud, and will appear before Westminster Magistrates' Court in London on Thursday.
"Tom Hayes attended Bishopsgate police station this morning where he was charged by City of London police with eight counts of fraud," the Serious Fraud Office (SFO) said in a statement here today.
The 33-year-old was arrested by police and the SFO last year alongside two other traders and has previously denied any wrongdoing.
In late 2009, Hayes left UBS to join Citigroup where he worked for less than a year.
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It remains unclear when the alleged offences took place.
Late last year, US prosecutors had charged Hayes over the rigging of the Libor rate.
Authorities in the US, Asia and the UK have been racing to secure convictions for firms and individuals that they believe manipulated the key benchmark banking rate.
The Libor rate is used to set trillions of dollars of financial contracts, including many car loans and mortgages, as well as complex financial transactions around the world.
However, the system has been found to be open to abuse, with some traders lying about borrowing costs to boost trading positions or make their bank seem more secure.
The Libor scandal erupted last year when Barclays bank was fined 290 million pounds by British and US regulators for attempted manipulation of Libor and Euribor inter-bank rates between 2005 and 2009.
Royal Bank of Scotland has also received heavy fines over alleged rigging of Libor - a flagship instrument used all over the world, affecting what banks, businesses and individuals pay to borrow money.
Last week, the British Bankers' Association (BBA), which compiles Libor submissions, said it would change how the interest rate is set, in order to avoid a repeat of last year's rigging scandal.
From July 1, publication of banks' individual submissions will be embargoed for three months to avoid "manipulation", the BBA said.