Contracts to buy previously owned U.S. homes rose modestly in April, a sign of stabilization in the housing market, which had been pummeled by higher interest rates and a harsh winter.

The National Association of Realtors said on Thursday its Pending Home Sales Index, based on contracts signed last month, increased 0.4 percent to 97.8. The increase was below economists' expectations for a 1.0 percent advance.

Sales stumbled last summer after the U.S. Federal Reserve signaled it would soon reduce economic stimulus efforts, pushing mortgage rates sharply higher. Rates have eased this year, but for many homebuyers they remain about seven tenths of a percentage point higher than they were in May of 2013.

Sales have now risen for two consecutive months. However, they fell 9.2 percent in the 12 months through April.

Contracts increased in the Northeast and the Midwest, but fell in the South and the West.