The backlog of unsold US homes surged to a record level in April and sales continued to decline as the dark clouds hanging over the residential property market showed few signs of lifting, a report revealed on Friday.

Existing home sales fell 1 per cent in April to a seasonally adjusted 4.89m annual rate, the National Association of Realtors said. The figure was a fraction less severe than economists had expected, but matched a record low set in January. Sales of previously owned homes were 17.5 per cent below the same period a year ago.

Inventories of unsold properties climbed by 10.5 per cent to 4.55m units, which at the present anaemic sales pace would take 11.2 months to offload - the most since the NAR began tracking combined statistics for single family homes and condos in 1999.

Meanwhile, inventories of unsold single family homes rose to a 10.7-month supply, the biggest since 1985.

The supply of unsold properties commonly rises in the spring. Nevertheless, the report contained few morsels for those looking for signs of a bottom in the housing market.

This burgeoning backlog of unsold properties has become a dead weight on the US real estate market, causing prices to spiral lower as a tide of foreclosures compounds the problem.

Buyers may be reluctant to enter the market as prices show few signs of stabilising and mortgages have become more difficult to obtain.

“With prices collapsing the incentive not to buy a home is increasing by the week, and with inventory showing no sign of improvement prices will keep falling,” Ian Shepherdson, chief US economist at High Frequency Economics, said.

The median sale price of previously owned homes was $202,300 last month, a drop of 8 per cent from a year ago but slightly higher than in March, the NAR report said.

House prices fell 1.7 per cent in the first three months of this year, the biggest quarterly drop on record, according to an Office of Federal Housing Enterprise Oversight report on Thursday.