WASHINGTON — After falling for six consecutive months, sales of existing homes posted an unexpected increase in February which might have reflected more aggressive price cutting by sellers in some parts of the country, a real estate trade group reported.

The National Association of Realtors said today sales of existing homes rose by 2.9 percent in February to a seasonally adjusted annual rate of 5.03 million units. It was the biggest increase in a year and caught economists by surprise. They had been expecting a small decline.

The trade group reported that the median existing sales price in February fell to $195,900. That was the largest year-over-year drop on records that go back to 1999.

Lawrence Yun, chief economist for the Realtors, said prices in some formerly hot markets in California and Florida were seeing significant price declines now as sellers try to attract buyers.

Analysts cautioned against reading too much into the one-month rise in sales. Many economists are predicting that the steep slump in housing will not bottom-out until later this year after prices fall further and allow huge levels of unsold inventories to be reduced.

"We're not expecting a notable gain in existing-home sales until the second half of this year, but the (February) improvement is another sign that the market is stabilizing," Yun said.

By region of the country, sales surged by 11.3 percent in the Northeast and were up 2.5 percent in the Midwest and 2.1 percent in the South. The only region of the country to see a decline in the sales was the West, where they dropped by 1.1 percent.