A further drop in the number of people putting their homes up for sale is pushing house prices higher, according to surveyors.
A report from the Royal Institution of Chartered Surveyors (Rics) says new instructions by sellers have fallen "deeper into negative territory".
Meanwhile the number of inquiries from would-be buyers remains unchanged.
As a result, most of the 308 Rics members who took part in the survey said house prices were now rising.
The monthly survey showed that the number of homes being put up for sale had fallen for the eighth time in the past nine months, and indicated that new instructions were falling at their fastest rate since May 2009.
Simon Rubinsohn, Rics chief economist, said: "It is conceivable that the decisive outcome to the election could encourage a pick-up in instructions to agents and ease some of the recent upward pressure on house prices, but it is doubtful that this will be substantive enough to provide anything more than temporary relief.
"Alongside an increased flow of second hand stock, it is absolutely critical that the new government focuses on measures to boost the flow of new build."
New upward trend
Not only have the Rics members in the survey seen prices rise recently across the UK, but most of them expect this trend to continue in the next 12 months.
UK house prices have been flat since July last year, according to the most recent report from the Office for National Statistics (ONS).
But more recent reports from Halifax and the Nationwide have suggested that prices have started to pick up again.
Those in the industry say that this is because not enough homes are being built to meet the demands of a fast-growing population.
Some lenders are tempting potential borrowers by offering mortgages with interest rates of less than 2%, fixed for as long as five years.
And the number of mortgages approved, but not yet lent, picked up again in February and March after slowing down last autumn, according to the Bank of England.
Those are traditionally a good indicator of near-term trends in activity in the property market.
Jeremy Blackburn, head of policy at Rics, warned that housing in the UK was now facing a national emergency.
"The last time we were building 300,000 homes was in 1963 under Harold Macmillan's Conservative government, which utilised both public and private building," he said.
"We need a coherent and coordinated house building strategy across all tenures.
"Introducing demand-side measures, such as extending 'Right to Buy', will not see the Conservatives deliver on their promise of one million homes by 2020," he added.