U.S. housing prices fell 4.2 percent in the first quarter of the year and are now at levels last seen in mid-2002, rating agency Standard & Poor's said Tuesday.

S&P/Case-Shiller's National Home Price Index was also down 5.1 percent compared with the first quarter of 2010.

Between February and March, prices declined in 18 of the 20 largest U.S. metropolitan areas.

Of those 20 cities, Minneapolis saw the steepest year-on-year descent, 10 percent; followed by Phoenix, down 8.4 percent; Chicago, 7.6 percent; Seattle, 7.5 percent; Tampa, 6.9 percent; and Charlotte, 6.8 percent.

"This month's report is marked by the confirmation of a double-dip in home prices across much of the nation," David M. Blitzer, chairman of the Index Committee at S&P Indices, said in a statement accompanying the data.

Home prices in Atlanta, Charlotte, Chicago, Cleveland, Detroit, Las Vegas, Miami, Minneapolis, New York, Phoenix, Portland and Tampa dipped to their lowest levels in the current cycle, Blitzer said.

"Atlanta, Cleveland, Detroit and Las Vegas are the markets where average home prices are now below their January 2000 levels. With a March index level of 100.27, Phoenix is not far off," he said.

"The rebound in prices seen in 2009 and 2010 was largely due to the first-time home buyers tax credit," Blitzer said. "Excluding the results of that policy, there has been no recovery or even stabilization in home prices during or after the recent recession."