During the weekend, German Chancellor Angela Merkel rebuffed pleas from the leaders of Spain, France and Italy on the concept of providing direct financial assistance to banks, rather than to governments, which adds to their debt burdens.
By close of trading, the Dow Jones industrial average shed 138.12 points, 1.09 percent, to 12,502.66. The Standard & Poor's 500 index gave up 21.30 points, 1.6 percent, to 1,313.72. The tech-heavy Nasdaq composite index lost 56.26 points, 1.95 percent, to 2,836.16.
On the New York Stock Exchange, 712 shares advanced and 2,346 declined on a volume of 3.1 billion shares traded.
The benchmark 10-year treasury note rose 21/32, pushing yields down to 1.607 percent.
The euro fell to $1.2502 from Friday's $1.257. Against the yen, the dollar fell to 79.66 yen from 80.43 yen.
In Tokyo, the Nikkei 225 index shed 0.72 percent, 63.73, to 8,734.62.
In London, the FTSE 100 index lost 1.14 percent, 63.04, to 5,450.65.
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