Stocks in the United State fell on Wednesday after minutes of a meeting of the Federal Reserve in July offered few clues on a time frame for a reduction in the Fed's bond-buying programme.
Officials said they were "broadly comfortable" with plans to scale back the programme, which is spending $US85 billion per month. However, the timing remains murky.
Chairman Ben Bernanke has indicated that the timing of the Fed's decision will be dependent on a healthy US economy.
Mortgage rates jumped sharply in June after Mr Bernanke hinted at plans to end the policy.
The Dow Jones Index fell more than 100 points or 0.7% to 14,898. The S&P 500 Index was down 10 points, or 0.6% to 1,643. The Nasdaq Composite fell 13 points or 0.38% to 3,600.
Earlier, the FTSE 100 in London was down 0.97%, the Dax in Frankfurt was down 0.18% and the CAC-40 in Paris was down 0.34%.
At 8.30am on Thursday, the New Zealand dollar was at 78.43 US cents, 87.43 Australian cents, 50.15 pence, 76.78 yen and 0.5876 euro.
Brent crude oil was trading at $US112.68 per barrel and gold was trading at $US1367 per ounce.