Campaigners have blamed former chancellor George Osborne for blocking stronger plans to tackle toxic air pollution, including more Clean Air Zones (CAZ) and extending their remit to private cars.
Environmental lawyers ClientEarth said documents disclosed during its renewed court action against the Government show that the Treasury watered down the national air quality plan, published last December.
George Osborne has now left the Government
Ministers were forced to produce that plan following a Supreme Court case last year, but ClientEarth is now challenging its adequacy in a new High Court case.
According to ClientEarth, documents show that ministers at environment department Defra drafted more ambitious plans but were overruled by the Treasury.
ClientEarth lawyer Alan Andrews said: ‘The former Chancellor, George Osborne has some serious questions to answer.’
The centrepiece of the national air quality plan is CAZs in five cities – Birmingham, Derby, Leeds, Nottingham and Southampton in addition to London’s Ultra Low Emissions Zone - with measures to deter some diesel vehicles.
According to ClientEarth, documents disclosed in the court case reveal that Defra officials considered 16 such zones necessary to bring air pollution to within legal limits as soon as possible.
ClientEarth said the Treasury also blocked the inclusion of private cars in any of these zones and vetoed a proposal to introduce fiscal reforms that would discourage the use of diesel.
During the current court case, ClientEarth counsel Nathalie Lieven QC said the Treasury wanted the ‘minimum’ measures necessary to achieve compliance and that cost was the overriding factor in decision-making.
She said: ‘What is absolutely clear is that the cost of the measures and the requirement to keep the costs to a minimum was, in the end, the factor that led to six mandatory Clean Air Zones.
‘All the evidence shows that, on the basis of the modelling carried out, six mandatory zones were not going to achieve compliance.’
A Government spokesperson declined to comment on ongoing legal proceedings but highlighted that it has 'committed more than £2bn since 2011 to increase the uptake of ultra-low emissions vehicles, support greener transport schemes and set out a national plan to tackle pollution in our towns and cities’.