Stocks flip-flop in early trade

Wall Street uncertain in early trading after previous day's big run. Bernanke comments on tap.

NEW YORK (CNNMoney.com) -- Stocks were mixed Tuesday as investors were cautious after the previous session's big run and ahead of comments from Federal Reserve Chairman Ben Bernanke.

The Dow Jones industrial average (INDU) added a few points in the early going. The S&P 500 (SPX) index was barely changed. The Nasdaq composite (COMP) fell 6 points, or 0.4%.

U.S. stocks climbed Monday, buoyed by optimism about the economic recovery. The Nasdaq rose to a six-month peak while the Dow and S&P 500 reached their highest levels in almost four months.

"It's going to take a powerful catalyst to [continue to] move us forward," said Art Hogan, chief market strategist at Jefferies & Co.

Economy: Federal Reserve Chairman Ben Bernanke is due to give his outlook on the economy to the Joint Economic Committee.

A reading on the services sector of the economy from the Institute for Supply Management, a purchasing managers' group, is also due out.

Banks: The financial sector will remain in focus as investors await the release of the results of the U.S. government'sstress tests on banks, which are due out Thursday.

At least 10 of the 19 big banks under review -- including Bank of America (BAC, Fortune 500) and Citigroup (C, Fortune 500) -- may need to boost their capital, according to a report in The Wall Street Journal. The number of reported banks that may need to boost their capital requirements has been fluctuating in the runup to the release of the results.

Companies: Swiss bank UBS (UBS) reported a $1.76 billion quarterly loss and said it remains cautious about the outlook because the global economy has continued to worsen.

Dow component Kraft Foods (KFT, Fortune 500) reported higher quarterly earnings that topped estimates. But revenue fell as the stronger U.S. dollar hurt sales overseas. Kraft shares rallied 6% Tuesday morning.

Fellow Dow component Walt Disney (DIS, Fortune 500) was expected to release results after the closing bell.

0:00 /00:51Manufacturing's decline slows

World markets: Stocks in Asia finished the session higher. Japanese and South Korean markets were closed for holidays. In European trading, shares in London were higher, while stocks in Paris and Frankfurt fell.

Oil and money: Oil fell 14 cents a barrel to $54.33. The dollar rose against the euro and the yen, but slipped versus the British pound.