Just 0.01% of the population own 8.3% of the land – while 46% own none.

The report concluded: "It is unfair that, while some individuals own hundreds of thousands of acres, others are unable to rent a small allotment plot.

"Much of the individual holdings, as well as those held by the Church of England and the Crown Estate, are likely to have areas that may be suitable for allotments."

Calling for a “Large Private Estates Commission” to map private land, the report added: "Local authorities would then be able to assess the suitability of this mapped land for, among other things, allotment and community garden sites."

In more urban areas – where the demand for allotments is highest – there are more than 10,000 hectares of vacant brownfield land which could be used, it said.

Across the UK, the top 1% of landholders own 70% of land. Meanwhile, the number of allotments has plunged from 1.4m in the 1940s to 200,000 in the present day.

The study also picks out Wirral Council's “Allotment Strategy 2007-2012” as the type of action plan more local authorities should draw up.