European markets are down sharply Monday. Treasury prices are rising, pushing yields near their lows for the year.
Traders fear that Greece could default on its debts, and European policymakers are divided over how to handle the crisis.
The resignation of a key European Central Bank official combined with worries over a new recession in the United States led to a large stock market sell-off on Friday.
Two hours before the opening bell, Dow futures are down 197 points, or 1.8 percent, to 10,745. S&P 500 index futures are down 20, or 1.7 percent, to 1,132. Nasdaq 100 futures are down 30, or 1.4 percent, to 2,133.