NEW YORK, May 29 (Xinhua) -- U.S. stocks opened sharply lower on Tuesday as investors digest latest economic data while keeping a close eye on Italy's political situation.

Shortly after the opening bell, the Dow Jones Industrial Average was down 174 points, or 0.70 percent, to 24,556.00. The S&P 500 decreased 16 points, or 0.59 percent, to 2,702.25. The Nasdaq Composite Index erased 3.34 points, or 0.04 percent, to 7,430.51.

On the economic front, the Conference Board Consumer Confidence Index increased in May, following a modest decline in April after a downward revision. The index now stands at 128.0, up from 125.6 in April.

The index measures U.S. sentiment on current economic conditions and expectations for the next six months. Consumer spending accounts for about 70 percent of U.S. economic activity, drawing economists' attention to the numbers.

Meanwhile, investors are concerned about Italian politics.

With an assertive move to put a temporary end to an 85-day-long stalemate, Italian President Sergio Mattarella on Monday named economist Carlo Cottarelli as Italy's new prime minister-designate.

Cottarelli was asked to form a technical cabinet able to lead the country to snap elections -- either in late 2018 or early 2019 -- after the efforts by anti-establishment Five Star Movement (M5S) and rightwing League to form a government failed on Sunday.

On Tuesday, the pan-European Stoxx 600 was down more than 1 percent, with all sectors and major bourses in negative territory.

The market was closed on Monday in observance of Memorial Day. Enditem