London Plan: Khan must review green belt

London mayor Sadiq Khan must embark on a review of London’s green belt according to the government-appointed inspectors tasked with reviewing the draft London Plan.

In his report to the mayor, the panel of three inspectors said Khan’s draft plan would fail to deliver the identified housing need of 66,000 homes a year because of an optimistic overreliance on small sites.

The inspectors said a target of 52,000 homes per year should instead be adopted, despite failing to meet the need for homes, because “the inescapable conclusion is that if London’s development needs are to be met in future then a review of the Green Belt should be undertaken”.

The conclusions are awkward for Khan as he was elected on a manifesto committing him to opposing development on the green belt which surrounds the capital. Political opponents have seized on the findings as evidence that Khan’s drive to densify already used land has effectively been a “war on the suburbs”.

The inspectors did not say that this plan should be held up while a review is undertaken, but instead that it should include a commitment to a future review in time for the next plan. But they also said the existing green belt policy – that all developments harming the green belt be refused – should be altered to make clear that special circumstances may allow green belt schemes to go ahead.

The Metropolitan green belt surrounding the capital covers 500,000ha in a ring around the capital, protecting it from development. Planners have long called for a review of the boundary, with the Adam Smith Institute calculating that one million homes could be built by releasing just 3.7% of it.

The inspectors’ report said the draft 66,000 homes-a-year target would be “setting up the Plan to fail”, which under government planning rules, would end up exposing London boroughs to speculative development when targets were missed.

The inspectors made these recommendations after concluding the mayor’s assessment that more than 245,000 homes could be built on small sites in the 10 years of the plan be slashed to just 119,000. They found that “the modelling of small sites is insufficiently accurate to give a true picture of the likely available capacity”.

The inspectors also recommended that Khan drop his long-standing opposition to a second runway at Heathrow, and include the scheme in the Plan.

Richard Brown, research director at Centre for London, said the “time was right” for a review of the green belt, even though it was “likely to prove more popular with planners than with national politicians or the general public.”

He said: “Reviewing the green belt would definitely be controversial, and care would be needed to ensure that it provided for good growth rather than environmentally ruinous sprawl.

Conservative Assembly member Andrew Boff said: “The planning inspectors have recognised that Sadiq Khan’s plans are little more than a war on the suburbs, and it is completely right to say that the mayor’s determination to overdevelop small sites is ‘neither justified or deliverable’.”

However, Boff said the inspector was wrong to try to force a review of green belt, saying that homes could be put on underutilised industrial land, and that dropping opposition to Heathrow expansion would be “entirely unacceptable.”