ClientEarth has launched a new legal challenge against the UK government due to its repeated failure to tackle illegal air pollution.

In this latest round of legal action, ClientEarth has lodged papers at the High Court in London seeking judicial review and has served papers on government lawyers.

As well as the UK Environment Secretary who is named as the defendant, Scottish and Welsh ministers, the Mayor of London and the Department for Transport will also be served with papers as interested parties in the case.

The UK sees an estimated 40,000 early deaths from air pollution every year. ClientEarth believes the government is in breach of a Supreme Court order to clean up air quality, having failed once again to take appropriate action in the face of this public health crisis.

ClientEarth won a judgment at the Supreme Court against the Secretary of State for the Environment, Liz Truss, in April last year. The ruling ordered her department to produce new air quality plans to bring air pollution down to legal levels in the “shortest possible time”.

The plans the government came up with, released on 17 December last year, wouldn’t bring the UK within legal air pollution limits until 2025. The original, legally binding deadline passed in 2010. The papers lodged with the High Court ask judges to strike down those plans, order new ones and intervene to make sure the government acts.

ClientEarth lawyer Alan Andrews said: “The government’s plans were an insult to the tens of thousands of people being made sick and dying from air pollution and failed to consider strong measures to get the worst polluting diesel vehicles out of our town and city centres.

“As the government can’t be trusted to deal with toxic air pollution, we are asking the court to supervise it and make sure it is taking action.”

A YouGov poll for ClientEarth this week revealed air pollution is Londoners’ biggest health concern, topping a list which included smoking, stress and alcohol.

In the survey, of more than 1,000 London adults, three out of four said they backed legal action to force the government to deal with air pollution.

ClientEarth is launching an appeal for donations to help fund our legal case. Those who support our action can join the conversation on social media under the new hashtag #no2dirtyair.

Alan Andrews added: “It is a disgrace that we have had to take further legal action to force the government to protect our health. It must act urgently to tackle this public health crisis.”