In a major speech, the Mayor will announce that City Hall will actively explore releasing parts of London’s green belt to help end the housing crisis
- Sadiq wants to forge a new consensus on planning to build the affordable housing Londoners need - including on parts of the green belt - at the same time as boosting biodiversity and increasing public access to genuinely green spaces
- Developing some green belt close to transport links in a strategic way could deliver hundreds of thousands of new affordable homes for Londoners
In a radical change of approach, the Mayor of London, Sadiq Khan, is today (Friday 9 May 2025) announcing that City Hall will be actively exploring the release of parts of London’s green belt for development.
In a keynote speech in Greenwich, Sadiq will say that his position on the green belt has changed because bold solutions are required to fix London’s housing crisis – which is having a profoundly damaging impact, particularly on families and younger Londoners.
To meet demand, London needs 88,000 new homes a year over the next decade: close to a million homes. The capital has never built this number of homes before, and only ever built at anything close to this rate when there was a housing boom across the country in the 1930s. The Mayor will say that we must be honest with Londoners that our current approach to only build on ‘brownfield’ (previously developed land) will never be enough to meet the scale of the challenge.
London’s green belt can often be low quality, poorly maintained and inaccessible to Londoners. Given the extent of the housing crisis and the nature of much of London’s green belt, Sadiq will argue the status quo is “wrong, out-of-date and simply unsustainable”. Releasing some carefully chosen areas of green belt for development could unlock hundreds of thousands of new homes for Londoners, including social homes, which would not only go a long way to ending the housing crisis but provide a huge boost to the economy.
Sadiq will highlight that the right transport and infrastructure will play a pivotal role in his new approach, enabling higher density developments near public transport connections. That’s why he will be working closely with UK Government on the investment London needs for both housing and transport, including the metro-isation of London’s rail lines and extensions to the Bakerloo line and Docklands Light Railway.
The Mayor will say he wants to forge a new consensus on planning that’s fit for 21st century London. He will argue that the idea you have to choose between housebuilding and the environment is a false choice. City Hall will attach conditions to any release of the green belt – not only to maximise the level of affordable housing and produce high-quality, energy-efficient homes, but to ensure there is an increase in biodiversity and public access to genuinely green spaces.
The Mayor will call on environmental campaigners and developers to work with him to enhance the environment and make London greener than ever before, at the same time as delivering the affordable and social homes London needs. He will acknowledge that this is a contentious issue and ask Londoners to keep an open mind while looking at the latest evidence – both on the damage the housing crisis is causing and the green belt.
The announcement comes as the Mayor launches a consultation to help shape the next London Plan, which sets out the Mayor’s vision for how the capital will develop over the next 20 to 25 years. The key objectives of the next London Plan will be fixing the housing crisis and delivering sustainable economic growth while protecting and improving the environment.
This work will build on the Mayor’s track record since taking office: completing more homes than at any time since the 1930s, using planning powers to drive the proportion of affordable housing in major developments up to 42 per cent, hitting the government target of 116,000 new genuinely affordable homes, taking council housebuilding to its highest level since the 1970s, and starting over 25,000 affordable homes in 2023 alone – the highest number since Greater London Authority records began.
On the profound damage being caused by the housing crisis and the need for bold action, Sadiq will say: “A generation of Londoners now simply can’t afford to rent, let alone buy a home. We have young professionals stuck living in their childhood bedrooms for years on end; Londoners having to endure cold, damp accommodation that isn’t fit for human habitation; couples reluctantly moving out of the capital to start a family; and London primary schools closing because young families have been priced out of the area. At the sharpest end of this crisis, Londoners are being forced to sleep rough on the streets and over 90,000 children are officially homeless.
“It breaks my heart. The damage the housing crisis is causing is pervasive and profound. We simply cannot let it continue. At stake is the fundamental promise of our city – the promise that if you work hard in London, London will work for you. It goes to the very heart of why I got into politics in the first place: to preserve the ‘London promise’ for future generations and to ensure that all Londoners, whatever their background, get the opportunities they need to reach their potential.”
On the need to build on the green belt, Sadiq will say: “We clearly face an extraordinary challenge. As Mayor, I'm determined to give it everything we've got – with a radical step-change in our approach. We'll be working with councils and others to secure as many new homes as we can on brownfield sites, both large and small, but we have to be honest with Londoners that this alone will not be enough to meet our needs.
“That’s why I’m announcing that City Hall’s new position will be to actively explore the release of parts of London’s green belt for development.”
On the myths about the green belt, Sadiq will say: “The perception many people have is that the green belt is all beautiful countryside, green and pleasant land, rich with wildlife. The reality is very different. The green belt can often be low-quality land, poorly maintained and rarely enjoyed by Londoners. Only around 13 per cent is made up of parks and areas that the public can access.
“So given the quality of parts of the London’s green belt and the extent of the housing crisis, I believe the status quo is wrong, out-of-date and simply unsustainable. Development on carefully chosen parts of the green belt - done in the right way - would allow us to unlock hundreds of thousands of good quality new homes for Londoners. This would not only go a long way to ending the housing crisis but provide a huge boost to our economy.
“As Mayor, I’m not willing to ignore such a prospect just because it might be politically difficult – not when the life chances of the next generation of Londoners are on the line.”
On making London greener at the same time as building on the green belt, Sadiq will say: “I want to make clear that I remain proud to be the greenest Mayor London has ever had, and I don’t see what I’m announcing today as running contrary to this.
“I can assure Londoners that we'll attach the right conditions to any release of the green belt. Not only will we always make the best use of land, maximise the level of affordable housing and produce high-quality, energy-efficient homes with good transport connectivity, but we’ll ensure we increase biodiversity and public access to good quality green spaces.
“I want to forge a new consensus on planning that’s fit for 21st century London, where we build the affordable housing we need - including on parts of the green belt - at the same time as increasing biodiversity and the amount of land that is genuinely green and accessible.”
On his message to environmental campaigners, Sadiq will say: “We’ve created or improved 900 hectares of green space in London since I become Mayor. We can take this experience and ensure we make London and the green belt greener in everything we do. As well as developers, I urge environmental campaigners to join me in this effort.
“We’ve worked closely together on creating the largest clean air zone in the world, on planting a record number of trees, on rewilding London and on many other climate measures – often in the face of opposition. Now let’s work together to achieve something truly ambitious: delivering the affordable housing we need while enhancing the environment and making London greener than ever before.”
Welcoming the Mayor’s bold approach, Deputy Prime Minister and Housing Secretary Angela Rayner commented: “We all know someone who has been affected by the acute and entrenched housing crisis we’ve inherited, and the picture in London is as stark as anywhere. A whole generation of Londoners will be able to tell you of the horror stories they've faced while trying to find a suitable home in our capital.
“We cannot end the housing crisis and build the 1.5 million homes we need without London being ambitious in its approach. That’s why the government welcomes the bold proposal announced by the Mayor today, which rises to the challenge of tackling London’s housing crisis. The Mayor of London has our backing to deliver the housing this city needs, in line with our ambition nationally, to unlock the dream of a secure home for a generation.”
London Councils chair Cllr Claire Holland added: “London is grappling with the worst housing pressures in the country and there is a desperate need to build new homes, particularly more affordable homes. Boroughs are resolutely pro-housebuilding and are committed to working with the Mayor and the government to boost housing delivery across the capital. We look forward to helping inform the development of the new London Plan to achieve this goal and ensure that it meets the needs of our local communities.”
Vauxhall and Camberwell Green MP Florence Eshalomi said: “As both a lifelong Londoner and a South London MP, I see the impact that the housing crisis has on our communities every week. It deprives too many of the basic right to a decent home and prevents young people in particular from building a life of their own. I welcome the Mayor’s commitment to building the homes that our city desperately needs and exploring proposals which will make this a reality.”
Generation Rent CEO Ben Twomey added: “Building new homes where people want to live is vital to protect Londoners from the eye-watering cost of renting. When housing costs are forcing too many of us into poverty and homelessness, it is right that the Mayor sets out his ambition to build the homes we need, including in parts of the green belt where appropriate. I encourage renters across the capital to have their say on the Mayor's proposals.”
‘Towards a new London Plan’ is available at www.london.gov.uk/towards-new-london-plan for responses by 22 June. Following this public consultation, the draft London Plan will be published in 2026 for another examination process, with formal adoption expected in 2028.
Notes to editors
- ‘Towards a London Plan’ sets out ideas to address issues around the quality and quantity of housing delivery, as well as the infrastructure needed to support it, while also ensuring that development and economic growth in the capital is inclusive and sustainable. It includes an update on current London Plan housing, jobs and transport infrastructure objectives to show the challenge presented by progress to date and UK Government housebuilding targets.
- Delivering much-needed homes can help create good jobs for Londoners, as new developments provide employment opportunities during construction and once completed. ‘Towards a London Plan’ explores how the next London Plan can support the recently published London Growth Plan, from boosting town centres and high streets to opening up job opportunities – particularly in key sectors like hospitality or cultural and creative industries, which have high growth potential but face economic challenges, as highlighted by recent UK Government interventions on London’s nightlife licensing.
- As more housing and a growing economy require strong transport connectivity, it also looks at improving the capital’s infrastructure and the importance of key projects like HS2 in helping London reach its potential. The London Growth Plan highlights that the next London Plan will need to prioritise extensions to the Bakerloo line, Overground and Docklands Light Railway, as well as tram upgrades and metro-isation of suburban rail.
- The London Plan sets housing targets for each borough, which they are required to meet. Boroughs all have their own local plans, aligned to the London Plan.
- The current London Plan expects all housing supply to come from ‘brownfield’ (previously developed land) based on annual city-wide target of 52,000 homes at the time. Current delivery rates of around 40,000 homes a year mean even a big increase from brownfield supply will not deliver the new annual target of 88,000 wholly within London’s existing urban extent. While the Mayor will continue to prioritise housing delivery on brownfield sites, the new document shows this alone can’t provide enough land and presents other ideas to plan for the homes Londoners need.
- UK Government National Planning Policy (February 2025) calls for green belt land in England to be reviewed and its boundaries altered to meet housing needs where they cannot be met in other ways. It also introduces a new concept of ‘grey belt’: green belt areas that have either been previously developed or don’t strongly contribute to green belt purposes (preserving the setting and special character of historic towns, stopping towns from merging into each other, and checking the unrestricted sprawl of London).
- While the Mayor has commissioned a London-wide green belt review in line with the government’s requirements, City Hall will go further than identifying grey belt and explore all possible options for unlocking enough land to meet housing need across the capital.
- The Mayor is clear that any green belt release must: be based on building sustainable, liveable neighbourhoods with access to public and active travel options; make the best use of land; deliver improved access to green space and biodiversity gains. Environment experts including the National Trust, Green Alliance and London Wildlife Trust will advise on mitigations and enhancements for green belt release, which this new consultation invites further ideas on.
- The London Plan includes a ‘threshold approach’ that incentivises development of affordable housing. This speeds up the planning process for schemes that provide higher levels of affordable housing, creating a fast-track route that avoids protracted viability debates and late stage reviews. It also helps to embed affordable housing requirements in land values, so that excessive valuations can no longer be used to drive down the number of affordable homes required in viability-tested schemes. First introduced through the Mayor’s Affordable Housing and Viability guidance in 2017, ‘Towards a London Plan’ now proposes ideas to ensure the threshold approach is still fit for purpose in light of current economic challenges.
- ‘Towards a London Plan’ looks at social rent and asks how London might deliver more affordable homes through estate regeneration, the growing built-to-rent model, purpose-built student accommodation and other specialist housing. It also considers affordable workspaces and whether planning policy could be adapted to better support businesses – particularly in key sectors like hospitality or the cultural and creative industries, which have high growth potential but face economic challenges.
- Please note that Florence Eshalomi’s comment in this release is given in her personal capacity as an MP, not as Chair of the APPG for London or MHCLG Committee.