Brownfield sites are being developed more than half a year faster than greenfield sites, according to research published by the Campaign to Protect Rural England (CPRE).

The charity said its research followed findings from a 2014 study which found that there are enough suitable brownfield sites for at least 1m new homes.

Carried out by construction consultants Glenigan, the new research covers 15 local authorities between March 2012 and December 2015.

The full findings, which were published on Wednesday (16 March), can be seen here.

They show that the time between planning permission being granted and construction work starting is generally the same for brownfield and greenfield sites.

But work on brownfield sites is completed more than six months quicker.

The CPRE said the new findings illustrates that prioritising investment in brownfield sites was a highly effective way of building much-needed homes.

It said many proposals included alongside a £2bn government pledge to regenerate brownfield sites would wrongly make it easier to build on greenfield land.

These proposals included a 'housing delivery test' that would force councils to release more land for development if housebuilders do not meet high housing targets, said the CPRE.

CPRE chief executive Shaun Spiers said the research undermined claims that brownfield was either too slow or inconvenient to develop in comparison to greenfield land.

"This government has strongly supported brownfield development," said Mr Spiers.

"Now it must show it has the courage of its convictions and usher in a brownfield revolution to tackle the housing crisis, benefit England's towns and cities, and save the countryside from inappropriate development.

"This new research shows that brownfield sites are developed more quickly than greenfield sites, giving the lie to the idea that developing a brownfield site must be difficult or unprofitable.

"What is needed now is for the Government to put all its energy behind getting houses built on derelict and vacant sites.

"Crucially, it must drop the idea that the way to get houses built is simply to make more countryside available. The evidence is that this will slow down house building, rather than speed it up."

The CPRE wants the government to amend the National Planning Policy Framework (NPPF) to prioritise the use of suitable brownfield sites in urban areas over greenfield.

It says this should include empowering councils not to allocate greenfield sites in local plans.

The CPRE also wants councils empowered to refuse planning permission on greenfield sites where these would compete with suitable brownfield sites.

It said the government should commit to seeing development started on 90% of suitable brownfield sites by 2020, rather than just aiming for planning permission on 90% of suitable sites by the same date.

The government announced plans for more than 70 councils to bring forward derelict and underused land for new homes earlier this month.

Communities secretary Greg Clark said 73 councils across England would pilot one of the new brownfield registers,

They registers will provide house builders with up-to-date and publicly available information on all brownfield sites available for housing locally.

Mr Clark said this would help speed up the construction of new homes.

It would also allow communities to draw attention to local sites for listing, including in some cases derelict buildings and eyesores that were primed for redevelopment.

Mr Clark said: "These councils will be at the forefront of these efforts to list land and encourage builders to deliver new homes for aspiring homeowners.

"But this is just the first step and I would urge councils to continue to offer up brownfield sites to deliver the homes their residents want and need."