Although new home sales fell to their lowest level on record in May, a report released today said housing prices started to rise in April.

The Standard and Poor’s/Case-Shiller report showed a 0.8 percent increase in prices in April, a 3.8 percent increase compared with April 2009, but the report said it was not a sign of sustainable recovery.

“Inventory data and foreclosure activity have not shown any signs of improvement,” said David Blitzer, chairman of Standard and Poor’s index committee. “Consistent and sustained boosts to economic growth from housing may have to wait till next year.”

According to the report, numbers are expected to drop on the next release, as some of the increase was fueled by the April 30 expiration of a federal tax credit for first-time home buyers, which induced consumers to buy more housing.

Of the 20 cities surveyed for the report, 18 posted increases with only Miami and New York declining. Prices in Chicago increased by 0.6 percent.