Green Belt: moving from protection to managed release
Within the adopted London Plan 2021, Green Belt land was treated as land which should be permanently protected, aligned to the NPPF at the time, allowing Green Belt boundaries to be altered only in exceptional circumstances, and directing growth towards brownfield land.
The Draft London Plan reflects the shift in national policy on Green Belt first introduced through the NPPF 2024. Draft Policy PV7 “Sustainable Development and Enhancement of Green Belt” recognises that selective Green Belt release may be necessary where it supports sustainable growth.
The Draft London Plan provides a more detailed definition of what constitutes a sustainable location for Green Belt release than previously seen in London policy. The strategy is focused on locations with existing or deliverable public transport accessibility, particularly those capable of supporting comprehensive proposals rather than isolated development parcels.
Residential-led development is expected to be closely linked to rail infrastructure, with the Plan requiring locations to be within walking distance (defined as being within 1,200 m) of railway stations and capable of supporting sustainable travel patterns (more aligned to the National Planning Policy Framework Reforms (2025) draft Policy GB7).
For industrial proposals, a sustainable location is judged to be within 2,500 m of certain junctions that access strategic highway networks with adequate capacity. This demonstrates that Green Belt release is not being promoted as a general housing and employment land supply mechanism, but instead as a targeted intervention in locations where development can function as an extension of London's existing urban structure.
Although this demonstrates a clear shift in policy and strategic release of Green Belt, it is noted that the Draft London Plan’s housing targets for ‘Greenfield Housing’ amount to only 56,100 over the next ten years – c. 10% of the total housing target for this period and 6% of the Government’s 880,000 housing target figure. During the consultation process there will likely be questions around whether this is enough to turn the dial on London’s housing crisis, or if the Green Belt lever should be pulled further to unlock more development potential.
Medium densification of Green Belt land
The Plan also signals support for a medium-density approach to development within the Green Belt. Rather than promoting either low-density suburban expansion or very high-density urban forms, the emphasis is on creating complete neighbourhoods that optimise land use while responding to landscape character and environmental constraints. This reflects a recognition that many Green Belt locations can contribute meaningfully to housing delivery through well-designed medium-density neighbourhoods that support local services, public transport viability and green infrastructure enhancements.
However, this could see residential densities on Green Belt land ranging from 90 to 160 dwellings per hectare with heights at 3 to 6-storeys. The aspiration is clear to optimise what can be delivered on Green Belt land to limit the need for release, but this raises the question of whether this generates a type of viable housing that meets the market demand for all outer London locations and is appropriate to local character.
A plan-led approach to Green Belt
Importantly, the Draft London Plan identifies a series of Green Belt Broad Locations for Growth, covering both residential-led and industrial-led development opportunities. The intention is that Green Belt boundary reviews and subsequent site allocations will be undertaken through a strategic planning process focused on these broad locations, providing a more co-ordinated approach to growth than would be achieved through individual speculative applications. This framework reinforces the Plan's objective that Green Belt change should be plan-led, infrastructure-led and strategically justified.
The Draft policy establishes a framework for identifying suitable locations, requiring any release to be plan-led rather than speculative. Draft Policy PV7 makes clear that Green Belt development should:
- Consider there to be strategic exceptional circumstances that would justify strategic scale releases of Green Belt land to deliver major residential and/or industrial-led schemes
- Review Green Belt boundaries in a manner that facilitates delivery of the expected capacity for those locations in line with the London Plan strategic objectives set out in policy MBUL1 ‘Spatial strategy’, including through subsequent site allocations to cover these areas
- Establish key masterplanning objectives and parameters for the identified broad location for growth, integrating the relevant aspects of part D of this policy together with necessary infrastructure priorities and enhancement opportunities identified through part C, reflecting these in site allocations.
Development proposals in the Green Belt will be expected to demonstrate strategic need, suitability of location, and that it is a suitable form of development that meets the nationally defined Golden Rules. The Draft Policy includes sustainable design criteria which demonstrates themes of land use optimisation, development of a comprehensive strategic cluster and landscape-led sustainable development.
All Boroughs with Green Belt land are required to “plan positively for its enhancement” recognising the fundamental importance and value that Green Belt still provides to the city.
The introduction of grey belt in London Plan Policy
The most notable difference from the 2021 Plan is the introduction of grey belt in London’s strategic planning policy, bringing the updated Plan in line with the current NPPF.
The Draft does not promote widespread grey belt development. Instead, it seeks to avoid fragmented, site-by-site release by directing any Green Belt changes through strategic planning and co-ordinated growth areas, with the exception to this being data centre development, reflecting the “different operational impacts of this use”.
The strategic planning approach seeks to achieve more efficient land use and stronger environmental outcomes than ad-hoc grey belt development.
Metropolitan Open Land remains strongly protected
While Green Belt policy changes significantly, protection for Metropolitan Open Land (MOL) remains largely intact from the 2021 Plan. The policy aim of Draft Policy PV6 “Metropolitan Open Land (MOL)” is to “establish the purposes of MOL, provide a framework for its protection and a positive strategy for its enhancement together with a mechanism for boundary alterations where specific tests are met”. Alterations to the boundary of MOL require “exceptional circumstances”.
One of the most significant distinctions between Green Belt and MOL in the Draft Plan is the extent to which MOL is insulated from the national grey belt agenda. The Plan explicitly confirms that national Green Belt policies relating to grey belt release do not apply to MOL. This creates a materially different policy position whereby land redesignated as MOL would continue to benefit from a much higher level of protection than Green Belt land, stating “national Green Belt policies requiring the consideration of releases to meet development shortfalls or in relation to grey belt do not apply to MOL”. This revised position removes the policy ambiguity that allows MOL to be treated as grey belt, as was allowed to be the case in the recent appeal decision 6005520 - Angsamus, Weigall Road, Greenwich.
The Draft policy also introduces a mechanism through which some Green Belt land may potentially be re-categorised as Metropolitan Open Land where it performs one of three important strategic open space functions. As a result, parts of London's existing Green Belt could move into a more protected designation rather than becoming candidates for development. These are not small-scale or isolated areas of potential re-categorisation – the evidence base document ‘London Green Belt Assessment: Metropolitan Open Land Opportunity Review (May 2026)' identifies vast swathes of Green Belt land as having the opportunity to be redefined as MOL.
In some cases, the clear majority of Green Belt within a Borough has the potential to be MOL, e.g. LB Waltham Forest, LB Ealing and LB Barking and Dagenham. This is an important consideration when assessing future development opportunities. Any land redesignated as MOL through the Local Plan making process would not benefit from grey belt provisions within the NPPF and would continue to require exceptional circumstances for boundary changes or development proposals.
Conclusions
The 2021 London Plan was founded on a brownfield-first strategy, seeking to accommodate virtually all growth within London's existing urban boundaries.
The Draft Plan retains brownfield development as the first priority but acknowledges that urban capacity alone is unlikely to meet long-term housing requirements. Consequently, it introduces a managed approach to Green Belt release while continuing to afford Metropolitan Open Land the highest level of protection.
Green Belt is no longer treated as just land beyond development, but as a strategic resource that could contribute to housing delivery where rigorous planning, infrastructure and environmental tests are satisfied. At the same time, Metropolitan Open Land remains firmly protected, with policy evolving more towards enhancement than relaxation.
Taken together, the proposals represent a more nuanced hierarchy of protection across London's open land designations. Green Belt is increasingly viewed as a strategic resource that may contribute to housing and economic growth where sustainability, infrastructure and environmental objectives can be met – although it could be questioned if the Draft London Plan utilises it enough to truly meet London’s development needs.
Metropolitan Open Land, by contrast, is being afforded a distinct and often stronger level of protection, particularly through the exclusion of grey belt provisions, meaning that in some circumstances re-categorisation to MOL may become a more significant constraint on future development than remaining within the Green Belt designation.
To discuss the Draft London Plan's evolving approach to Green Belt and Metropolitan Open Land, please get in touch with Kate Dowdall or Joanna Ede.
6 August 2026
[1] London Green Belt Assessment Greater London Report
[2] London Green Belt Assessment Metropolitan Open Land Opportunity Review
