The Government has been urged to implement clean air zones as quickly as possible after the Court of Justice of the European Union ruled the UK has “systematically and persistently” exceeded legal limits for nitrogen dioxide (NO2) since 2010.

The court found the UK has also failed against its legal duties to put plans in place to tackle the problem in the shortest possible time.

The UK could now face fines if it still fails to take action to comply.

Katie Nield, lawyer at environmental law charity ClientEarth, said: “The government has been dragging its feet for too long on the air pollution crisis, downplaying the problem and passing the buck to local authorities.

“To tackle harmful nitrogen dioxide pollution quickly, the evidence clearly shows that clean air zones, which are designed to keep the most polluting vehicles out of the most polluted parts of town, are the most effective solution.

“It’s up to the UK Government to work with local leaders to make sure these schemes are put in place as quickly as possible, alongside help and support for people and businesses to move to cleaner forms of transport.

“While authorities dither and delay on action to get the most polluting vehicles out of our towns and cities, people’s lives are being ruined by toxic air.”

Nield says that although the UK has left the EU, these pollution limits remain in national law so the government is still bound buy these rules.

If the UK then still fails to comply within a reasonable period, the European Commission could issue a letter of formal notice requiring the UK to remedy the situation.

If the UK fails to do so, the Commission could bring the matter before the CJEU a second time, seeking to have financial penalties imposed, although there remains some uncertainty whether it will have the power or the inclination to do this, now the UK is no longer part of the EU.

Numerous cities had announced plans to introduce CAZs, but in April last year the Government announced their introduction would be delayed until after the UK overcomes the Covid-19 pandemic.

However, many areas are still putting proposals together, with Bristol City Council agreed its proposals for a CAZ last week.

This would require drivers of all older, non-compliant vehicles to pay a daily fee to enter the zone.

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