In afternoon trading in New York, the Dow Jones Industrial Average gained 0.04 per cent. Gains in shares of Exxon Mobil and Chevron outweighed declines in shares of Microsoft and Boeing, lifting the Dow.
The Standard & Poor's 500 Index fell 0.09 per cent, while the Nasdaq Composite Index dropped 0.51 per cent.
There were more signs of strength in the US economy. Housing starts soared 22.7 per cent to a 1.09 million annualised rate, the highest since February 2008, according to Commerce Department data.
"The economy seems to be picking up and there's quite a lot of pent-up demand," David Sloan, a senior economist at 4Cast in New York, told Bloomberg News. "Even if the Fed does start to taper, I think the housing market will prove resilient."
Indeed, some said the Fed should begin easing its pace of bond-buying now.
"The last piece of the economic puzzle is falling into place and the expansion is assured. The last argument against tapering fell today, let's hope the Fed hears the news," Chris Rupkey chief financial economist at Bank of Tokyo-Mitsubishi UFJ in New York, told Reuters.
Meanwhile shares of FedEx, considered an economic bellwether, were flat at US$139.05 after the company posted net income that fell short of analysts' estimates, even as it lifted the range of its full-year earnings forecast.
FedEx is "on track to be where we need to be by the end of 2016," FedEx Chief Financial Officer Alan Graf said on a conference call with analysts and investors, Bloomberg reported. "We are managing very aggressively the tradedown in international."
In Europe, the Stoxx 600 Index finished the session with a 0.9 per cent increase from the previous close. The UK's FTSE 100 eked out a 0.1 per cent gain, while France's CAC 40 climbed 1 per cent and Germany's DAX added 1.1 per cent.