WASHINGTON • Permits for future U.S. homebuilding tumbled to a five-month low in April, suggesting the housing market was slowing as rising mortgage rates contribute to reduced affordability for entry-level and first-time buyers.

But the report from the Commerce Department on Wednesday also showed a record backlog of houses still to be constructed, indicating the moderation in homebuilding would be marginal.

Homebuilding was already being constrained by soaring prices as well as shortages of materials. The housing market is the sector of the economy most sensitive to interest rates, with building permits a leading indicator for the sector.

Building permits dropped 3.2% to a seasonally adjusted annual rate of 1.819 million units in April, the lowest level since last November. They rose 3.1% on a year-on-year basis. Economists polled by Reuters had forecast building permits would decrease to a rate of 1.812 million units.

The decline was concentrated in the single-family housing segment, where permits plunged 4.6% to a rate of 1.110 million units, the lowest level since last October. Permits for buildings with five units or more fell only 0.6% to a rate of 656,000 units.

A survey on Tuesday showed the National Association of Home Builders/ Wells Fargo Housing Market Index dropped to the lowest level in nearly two years in May. Builders blamed the fifth straight monthly decline in sentiment on soaring prices for building materials as well as rapidly rising mortgage rates.

The 30-year fixed-rate mortgage averaged 5.30% during the week ended May 12, the highest since July 2009, according to data from mortgage finance agency Freddie Mac.

The U.S. central bank has hiked its policy interest rate by 75 basis points since March. The Fed is expected to increase that rate by half a percentage point at each of its next policy meetings in June and July.

“Higher mortgage rates would at a minimum create uncertainty over the path of housing demand and discourage builders from taking out speculative housing permits,” said Isfar Munir, an economist at Citigroup in New York.

Cooling housing demand was reinforced by a separate report from the Mortgage Bankers Association on Wednesday showing applications for loans to buy a home dropped 12% last week from the prior week. They were down 15% on a year-on-year basis.

Housing starts slipped 0.2% to a rate of 1.724 million units last month. Single-family housing starts plunged 7.3% to a rate of 1.100 million units, also the lowest level since last October.