European stocks sank after Federal Reserve Chairman Ben S. Bernanke said the bank may end bond purchases next year if the economy strengthens in line with forecasts. U.S. index futures and Asian shares slid.

The Fed will probably taper its stimulus measures later in 2013 and halt bond purchases around mid-2014 as long as the world's largest economy performs in line with Fed projections, Bernanke told reporters yesterday in Washington after a two-day meeting of the Federal Open Market Committee.

The central bank said it will keep buying bonds at a pace of $85 billion a month, and repeated that it's prepared to increase or reduce the pace of purchases depending on the outlook for the job market and inflation.

A gauge of basic-resources shares was the worst performer on the Stoxx 600. Rio Tinto and BHP Billiton Ltd., the world's largest mining companies, lost 4.5 percent to 2,675 pence and 3.8 percent to 1,744 pence, respectively.

The preliminary reading of a Chinese purchasing managers' index for June released today by HSBC Holdings Plc and Markit Economics was 48.3, missing economists' estimates of 49.1. A number below 50 indicates contraction.

Randgold Resources Ltd. tumbled 5.9 percent to 4,372 pence as gold slid to the lowest since January 2011. Polymetal International Plc, a Russian gold and silver producer, slid 4.5 percent to 587 pence.

Swatch and Cie. Financiere Richemont SA fell 3.7 percent to 514.50 Swiss francs and 3.3 percent to 82.30 francs, respectively. Swiss watch exports fell 3.9 percent in May from a year earlier, the Federation of the Swiss Watch Industry said.

FTSE 100 6,203.63 -145.19 -2.29%

CAC 40 3,745.69 -93.65 -2.44%

DAX7,999.33 -197.75 -2.41%