The pandemic has led to a quarter fewer properties being listed for sale in England and Wales last month compared to a year ago, according to OnTheMarket data.

However, the shortage shows variations across types of dwellings and across the country, says the property portal.

The number of houses listed for sale was 33% lower over the 12-month period, while the number of flats for sale was 7% higher.

Knight Frank analysis of the data says that the problem is “more acute in parts of the country that have experienced stronger demand due to successive lockdowns”.

Among house listings, the volume was 3% down in London, compared to a drop of 42% in south-west England, the survey says.

The report explains that in January and February there was uncertainty over new Covid variants with the vaccination programme was in its early stages. Also, many parents were home-schooling.

Knight Frank says: “All of which meant new sellers were reluctant to list their property and we are seeing the effects of that now.”

It adds: “When demand escalated sharply in March, supported by the original stamp duty deadline at the end of the month, the best properties sold relatively quickly.

“As those properties went under offer, sellers hesitated as they were unable to find anywhere to move into themselves, exacerbating the supply shortage and putting upwards pressure on prices.”

Knight Frank head of UK residential research Tom Bill adds: “The current supply shortage represents a bumpy exit from the pandemic and tells us very little about how the property market is going to perform over the next 12 months.

“The last year has shown the importance of looking beyond short-term distortions in the property market.”

However, the estate agent believes “the imbalance” will correct itself as the number of appraisals rises.

It says the number of owners seeking the market price of their properties lifted above the level seen in January 2020 for the first time in six months in March.

Last January was marked by a pick-up in demand and supply following the December 2019 general election.

The report adds that the total available supply also increased for the first time in six months in March although it was still 15% down on last January.

However, Knight Frank does not believe the shortage will lead to an asset price bubble.

The agent says: “There has been little evidence of exuberance around prices against the backdrop of the global pandemic.

“The number of properties that exchanged below the guide price was 68% in March this year, compared to 74% last March. The rest were at or above the asking price.”