Timeline: Swiss battle with U.S. tax authorities over UBS

(Reuters) - A Swiss tax deal with the United States, crucial to the future of UBS, moved closer to legislative sign-off on Tuesday after the lower house of parliament backed the deal.

Following is a timeline of major events during the tax row:

2008

June 19 -- A former UBS banker who once smuggled a client's diamonds into the United States in toothpaste pleads guilty, as part of a broader tax evasion probe of UBS, to helping a billionaire hide $200 million from U.S. tax authorities.

October 16 -- UBS says to sell 9.3 percent stake to Swiss government for 6 billion Swiss francs ($5.55 billion) and put $60 billion of toxic assets into a new central bank fund.

November 12 -- Raoul Weil, head of UBS AG's wealth management business, charged with conspiring to help thousands of Americans hide $20 billion from U.S. authorities in Swiss bank accounts.

2009

February 10 -- Posts a 2008 loss of 19.7 billion francs, the biggest ever for a Swiss company. Cuts 2,000 jobs.

February 18 -- Swiss regulator FINMA orders UBS to identify certain U.S. clients to settle criminal fraud charges that it assisted rich Americans to evade taxes.

February 19 -- U.S. tax authorities say they are still pursuing a civil lawsuit seeking to access details on 52,000 UBS clients.

February 20 --UBS says could go out of business if it complies with an order to reveal the names of suspected U.S. tax dodgers.

April 2 -- U.S. authorities arrest and charge an accountant in Florida in the first of what they say could be a series of tax evasion prosecutions of American clients of UBS.

July 10 -- CEO Oswald Gruebel sends a memorandum to bank's top executives saying it could not comply with the U.S. request to disclose the identity of the 52,000 account holders.

August 18 -- A filing in a U.S. federal court shows U.S. criminally investigating over 150 U.S. clients of UBS.

August 19 -- Swiss say will hand over details of about 4,450 bank accounts to U.S. authorities as part of the deal to settle the UBS tax case. It effectively ends a separate civil lawsuit by U.S. authorities that sought up to 52,000 account names.

2010

January 8 -- Bradley Birkenfeld, the former UBS banker who became in whistleblower in the U.S. government's tax probe, starts a 40-month prison term.

January 8 -- A Swiss court rules that regulator FINMA broke bank secrecy law when it ordered UBS to hand over the files of nearly 300 clients to U.S. authorities.

January 22 -- A UBS client wins a Swiss court appeal to prevent her account data from being given to the U.S. authorities, throwing doubt on Switzerland's ability to deliver details of 4,450 UBS client accounts to the United States.

January 27 -- The Swiss government says it will talk to U.S. authorities in a bid to resolve the legal impasse. Says one step could be to seek retroactive approval from parliament.

February 24 -- Swiss government to ask parliament to turn a deal with Washington into binding law, plugging a legal hole stopping Berne from honoring the agreement.

April 15 -- Seven former wealthy U.S. clients of UBS are charged with filing false tax returns, collectively hiding more than $100 million held offshore in Swiss accounts.

May 31 - A 360-page report by two parliamentary committees slams the Swiss government saying it failed to act swiftly to prevent the credit and tax crisis that endangered UBS.

June 3 - Switzerland's upper house backs the U.S. tax deal, which is yet to be approved by the parliament's lower house.

-- The upper house also votes against allowing a referendum on the deal.

June 8 - Swiss lower house rejects the Swiss-U.S. tax deal over UBS, contradicting the vote of the upper house.

June 15 - The lower house approves the deal in its second vote but calls again for a referendum, sending the deal back to the upper house and delaying a final, decisive vote expected on June 18.

(Reporting by Sam Cage, Lisa Jucca, Jason Rhodes, Catherine Bosley and David Cutler, London Editorial Reference Unit; editing by Simon Jessop)