VW, Daimler, BMW and Opel made the decision at a summit with leading politicians in Berlin. They have been under pressure since the diesel emissions scandal two years ago exposed how VW and – it is suspected – other manufacturers have been cheating the testing regime.

The pressure on carmakers further increased last week when a court in Stuttgart – one of the country’s pollution hotspots – upheld a plan to ban older diesel cars from the city.

But environmental campaigners said the carmakers had not gone far enough.

Areeba Hamid, a clean air campaigner for Greenpeace said they were “clutching at straws.”

“Independent research has shown that some of these diesel cars emit up to 18 times more nitrogen oxide than the legal limit, so reducing it by 30% is nowhere near enough.

“This means that people across cities will continue to be exposed to the dangerous health impacts of air pollution for much longer.”

She said if the car makers were serious about reducing their role in the air pollution crisis they should ditch diesel and invest in electric cars.

Volvo last month became the first carmaker to announce all its new cars would be electric or hybrid from 2019.

But other leading carmakers have yet to follow their lead. At the Berlin summit the car companies met government ministers and regional leaders and emerged with details of the plan to retrofit 5.3m cars to reduce emissions. The carmakers said they would cover the cost of the upgrades.

Ugo Taddei, a clean air lawyer for environmental group Client Earth, who have taken legal action in several German cities over illegal levels of air pollution from diesel traffic, said: “This is a pitiful attempt by a discredited car industry to get itself off the hook for creating an endemic problem. The solution proposed is far too little, far too late.”

Taddei said the retrofit would cut NOx pollution by a maximum of 30%. “That’s a drop in the ocean, considering that Euro 5 and Euro 6 diesel vehicles emit on average five to seven times more NOx than the legal limits.

“Retrofitting has just been deemed an inadequate answer to the air pollution crisis by a German court. It cannot form the backbone of the national response to the problem … national authorities must roll up their sleeves and truly solve the air pollution problem caused by diesel vehicles in the shortest time possible.”

Anger is growing in German cities over poor air quality with several municipalities considering bans on older diesel vehicles.

But with an election looming, politicians appear nervous about upsetting drivers of the 15m diesel vehicles or taking on the car industry, which provides about 800,000 jobs.

Environment minister Barbara Hendricks said on Wednesday: “We expect a new culture of responsibility from carmakers.” She said the software updates were just a first step in cutting emissions.

Jenny Bates, Friends of the Earth air pollution campaigner, said: “If manufacturers can fix car software to help reduce pollution, why haven’t they done this already? The German car makers’ announcement is little more than tinkering under the bonnet following the diesel-gate scandal they were largely responsible for.”

The 5.3m cars to be retrofitted include 3.8m VW vehicles, 900,00 Daimler cars and 300,000 BMWs.

The car companies also offered an incentive for drivers who want to swap diesel cars for cleaner models. BMW said it would start an EU-wide renewal campaign for older vehicles that cannot be fixed with the software.

Air pollution now kills 3.3 million people prematurely worldwide every year with emissions from diesel engines among the worst culprits. A joint investigation by the Guardian and Greenpeace showed hundreds of thousands of schoolchildren across England and Wales are being exposed to illegal air toxicity levels from diesel vehicles.

In the UK a class action against VW over the emissions scandal has attracted more than 35,000 claimants.

Sandra Laville

This article first appeared on the Guardian

edie is part of the Guardian Environment Network

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