(Adds background on tax clampdown in paragraphs 4-5)
BOLOGNA, Italy Dec 13 (Reuters) - Raoul Weil, an ex-UBS banker charged by U.S. authorities for allegedly helping Americans dodge taxes via secret Swiss bank accounts, was being extradited on Friday to the United States from Italy to face a trial likely to reignite debate on tax fraud.
Weil, a 54-year-old Swiss citizen who was once the third-highest ranked executive at Zurich-based wealth manager UBS, was arrested in mid-October while holidaying with his wife at an upscale hotel in the northern Italian city of Bologna.
One of his lawyers and a judicial official told Reuters Weil had left Dozza prison in Bologna early on Friday and was being extradited to the United States. The judicial source said Weil was already on a flight to America.
His trial could help the United States and other Western countries step up their hunt for individuals and companies that use opaque offshore financial centres to avoid paying taxes, tax experts say.
While a global fight against tax cheats has forced offshore centres in Europe to embrace greater transparency, tax experts say much still needs to be done to ensure financial centres in Asia and the Middle East come on board.
Court records from the U.S. District Court in Florida showed Weil is due to appear at a hearing in Fort Lauderdale at 1100 EST on Dec. 16. If found guilty he could face up to five years in jail for allegedly conspiring to defraud the United States.
Weil's lawyer in the United States, Aaron Marcu of Freshfields Bruckhaus Deringer, declined to comment.
A spokeswoman from the U.S. Justice Department had no immediate comment.
U.S. authorities issued an international arrest warrant for Weil in early 2009, just months after he was charged for allegedly conspiring to help 17,000 American clients of UBS to avoid taxes. Weil denies any wrongdoing.
Weil was declared a fugitive by the United States, which issued an international arrest warrant for him. That meant the banker could not travel outside his native Switzerland without risking arrest. Weil did not work for more than a year, eventually joining Reuss, a tiny private bank in the Swiss canton of Aargau, near Zurich.
Weil's indictment in November 2008 was a landmark in efforts by U.S. authorities to clamp down on the alleged use of offshore Swiss bank accounts by tax dodgers.
In early 2009, UBS, the world's biggest wealth manager, agreed to pay a fine of $780 million euros to settle a tax fraud dispute with the United States. The deal also involved UBS passing on thousands of client names to U.S. authorities, a breach of Switzerland's treasured bank secrecy traditions.
(Additional reporting by Howard Goller and David Ingram; Editing by Lisa Jucca, David Holmes and Anthony Barker)