Ministers were under a court direction to produce tougher draft measures to tackle illegal levels of nitrogen dioxide pollution, which is largely caused by diesel traffic, by 4pm on Monday. The government’s original plans had been dismissed by judges as so poor as to be unlawful.

But following the announcement by Theresa May of a general election on 8 June, ministers lodged a lengthy application to the court late on Friday. It is understood it asked judges to allow them to breach the Monday deadline to “comply with pre-election propriety rules”.

The new draft would be submitted in June, after the election, with a full policy not produced until September.

Lawyers from environmental law group ClientEarth, which successfully took the government to court over its air quality plans, said the move was unacceptable, adding it was discussing its next move.

James Thornton, the group’s CEO, said: “The unacceptable last-minute nature of the government’s application late on Friday night, after the court had closed, has meant that we have spent the weekend considering our response.

“We are still examining our next steps. This is a question of public health and not of politics and for that reason we believe that the plans should be put in place without delay.”

The government lodged the lengthy application shortly before 7pm on Friday, which was too late for the court to accept. It was due to be considered by the court on Monday.

But ClientEarth said it was unlikely there would be a hearing on Monday as they would need time to respond to the government’s arguments, although the judge could order an emergency session.

The scale of the air pollution crisis was revealed in a joint Guardian-Greenpeace investigation this monthshowing hundreds of thousands of children were being educated within 150 metres of a road where levels of nitrogen dioxide from diesel traffic breached legal limits.

Last week figures obtained by Labour showed that more than 38 million people, representing 59.3% of the UK population, were living in areas where levels of nitrogen dioxide pollution were above legal limits.

Research consistently shows that exposure to traffic fumes is harmful to children and adults. Children are more vulnerable because their lungs are still developingand exposure to nitrogen dioxide reduces lung growth, causes long-term ill-health and can result it premature death.

Nitrogen dioxide emissions from diesel traffic cause 23,500 of the 40,000 premature deaths from air pollution each year, according to figures from the Department for Environment, Food and Rural Affairs (Defra). In April last year, MPs said air pollution was a public health emergency.

Thorton said: “Whichever party ends up in power after 8 June will need this air quality plan to begin finally to tackle our illegal levels of pollution and prevent further illness and early deaths from poisonous toxins in the air we breathe. The government has had five months to draft this plan and it should be published.”

Shadow environment secretary Sue Hayman said Labour would introduce its own air quality plan, “within the first 30 days” if it won the election.

“Labour will bring forward a new Clean Air Act, setting out how we would tackle air pollution that NHS experts say contributes to 40,000 premature deaths every year. With nearly 40 million people in the UK living in areas with illegal levels of air pollution, it is simply not acceptable for ministers to hide behind the general election to delay publishing plans to improve air quality.”

She dismissed the government’s bid to delay publishing its plan.

“Purdah rules exist to stop one party using the machinery of government for their electoral advantage, not to be used as an excuse to delay acting on vital public health matters. We trust that the court will recognise this.”

A Defra spokesman said: “We are seeking an extension to comply with pre-election propriety rules.”

Matthew Taylor

This article first appeared on the Guardian

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