The people of Britain's cities can finally look forward to breathing clean air

In what has been described as a "historic" judgement, the Supreme Court has ruled that the Government must finally meet air quality standards set by European law.

Under previous plans, levels of nitrogen dioxide in cities like London, Birmingham and Leeds were not going to meet the standards set by the European Commission's Air Quality Directive until 2030.

Since 2010, the UK has therefore effectively been in breach of European law - with levels in central London three times higher than those deemed safe.

However, after a five year court battle, launched by environmental campaigners at ClientEarth, the Supreme Court ruled on Tuesday morning that the Department for Environment, Food and Rural Affairs (Defra) must submit new plans to the European Commission "no later than 31 December 2015".

Air pollution kills tens of thousands of people in this country every year. We brought our case because we have a right to breathe clean air and today the Supreme Court has upheld that right.

This ruling will benefit everyone's health but particularly children, older people and those with existing health conditions like asthma and heart and lung disease.

The next government, regardless of the political party or parties which take power, is now legally bound to take urgent action on this public health crisis.

• Alan Andrews, ClientEarth lawyer

ClientEarth estimates that air pollution in the UK kills 29,000 people each year - more than obesity and alcohol combined - while the WHO believes pollution costs the UK economy £54bn annually.

Responding to the news, the Green Party's local transport spokesperson Caroline Russell said: "It is scandalous that [the Government] have delayed so long knowing the very serious public health impact of their failure to act.

"The speed of the judgement highlights the urgency of the issue. The seven month timescale for Defra to produce a plan to cut emissions must now concentrate minds and lead to immediate and widespread measures to clean up our air."

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