** Shares of U.S. regional banks drop as Fitch's downgrade
of U.S. government's credit rating rattles markets
** KBW Regional Banking index .KRX drops 1.6%
** PacWest Bancorp PACW.O , KeyCorp KEY.N and Western
Alliance Bancorp WAL.N down between 2.6% and 2%
** Fitch on Tuesday downgraded the U.S. government's top
credit rating to AA+ from AAA
** Shares of JPMorgan Chase JPM.N , Bank of America
BAC.N , Wells Fargo WFC.N , Citigroup C.N , Goldman Sachs
Group GS.N and Morgan Stanley MS.N down between 0.7% and
1.5%
** Banks have been navigating a tough regulatory period in
the aftermath of the crisis earlier this year, as federal
government agencies propose an increase in capital requirements
for the big lenders
** S&P 500 index .SPX is down 1.3%
(Reporting by Niket Nishant in Bengaluru)