A report from the Campaign To Protect Rural England said homebuilders are using ‘viability assessments’ to force through developments with minimal affordable housing.

This way developers can increase their profits, the CPRE pointed out. The organisation said developers are “gaming” the planning system, which allows them to draw up an assessment to show a development is no longer financially viable with the number of required affordable homes.

Local authorities grant planning permission to applications on the condition that a certain number of affordable homes are built but these can be overturned by a viability assessment study.

Many councils’ targets of achieving 35 to 40% affordable homes per development are being routinely missed because of this, the report out on Tuesday stated.

Paul Miner, planning campaign manager at CPRE: “If we don’t change things this will just get worse.

“The next government must reduce the power of these viability studies, stop highly profitable developers gaming the system and give councils the hard cash to start building houses again.”

Miner said you have to “look at those developers who continually use shady tactics to renege on promises to build affordable homes and new community infrastructure”.

“These are often the promises that win them permission in the first place.”

This is affecting the number of homes built in rural areas, the CPRE said.

In 2011-12, 35% of homes built were affordable in rural areas. This has dropped to just 16% in 2015/16 – a year in which Department for Communities and Local Government figures show councils built only 1,890 homes across the country.

CPRE’s research also shows that five of the 15 most unaffordable districts outside London have met their most recent lowest affordable housing target.

Andrew Whitaker, planning director at the Home Builders Federation, said: “The private sector currently provides around 40% of all affordable homes built in this country via cross subsidy from private sales.