From Reuters.com:
 
A looming court case against Swiss bank  UBS AG could prove a stumbling block to the United States and Switzerland  clinching a tax agreement this week.
Switzerland, whose private banks manage  around $2 trillion of foreign wealth, aims to secure 12 new bilateral  tax deals by the end of 2009 which could allow it to be removed from  an OECD "grey list" of states which need to improve tax cooperation  and avoid possible sanctions from G20 nations. 
It has already secured five agreements,  with Denmark, Norway, France, Mexico and one other unnamed country,  and plans to put the issue to a referendum. Talks between Swiss and  U.S. officials restart in Washington on Tuesday.
Swiss President Hans-Rudolf Merz has  asked U.S. Treasury Secretary Timothy Geithner to drop a tax evasion  case against UBS in return for a new tax accord, which might struggle  for ratification in Switzerland if the U.S. Internal Revenue Service  (IRS) persists with its pursuit of the bank. 
"We believe there has to be some kind of agreement before July 13 when the IRS and UBS are due to take part in a mini-trial," said analyst Teresa Nielsen at Vontobel, adding this could even come in an 11th hour deal on July 12.
