It has been reported that doctors and other health professionals are urging Sadiq Khan to ban diesel vehicles from the capital due to fears over pollution.
Doctors Against Diesel claim 9,400 Londoners a year die prematurely from breathing in toxic fumes from diesel engines.
The group of hundreds of health professionals and medical students launched their campaign in central London’s Euston Road, one of the most polluted roads in the capital.
Paris, Madrid, Mexico and Athens have all introduced a ban on diesel vehicles by 2025.
However, many opponents to the campaign suggest the plans are not only impractical, but could backfire.
RAC roads policy spokesman Nick Lyes has previously outlined his organisation’s stance on diesel cars, claiming that suddenly demonising diesel vehicles as a whole is “extremely short-sighted.”
He said: “Some of the newest diesel vehicles on the road are also some of the cleanest, and diesels will also play a role in helping to reduce CO2 emissions, which contribute to man-made climate change.
“The Government should instead find ways to encourage motorists to switch from the most polluting vehicles to cleaner modern vehicles, rather than punishing existing owners.
“They must also look to stimulate the modernisation of bus and taxi fleets, which can be the worst polluting vehicles in city centres.”
The London mayor has already stated he wants to get rid of diesel buses by 2018.
According to a spokesman for the mayor, Mt Khan has no legal powers to ban cars in London and is calling on the government “to face its responsibility and implement a national diesel scrappage scheme now.”
“The mayor has more than doubled air quality funding and is doing everything in his power to tackle London’s toxic air and rid the city of the most polluting vehicles, but he cannot do this alone’” the spokesman added.
In London, nearly 40% of all nitrogen oxides emissions and PM10 pollution, which is linked to decreased lung function, comes from diesel vehicles, according to the campaign.
Greenpeace campaigner Areeba Hamid said: “The number of people affected by air pollution in the capital is alarming and our health professionals have to deal with the consequences every day.
“Today, they have come together to demand for bold action, which can make a real difference to the air we breathe. The days of dirty diesel are over, governments need to support clean transport and hold car companies accountable for selling products that exceed legal and health limits.”
According to the BBC, Edmund King, president of the AA, said: “We all want to clean up air quality but you’ve got to give time, you’ve got to give incentives.
“Yes get rid of the worst offenders but I think a blanket ban would just backfire.”
A spokesman for the Society of Motor Manufacturers and Traders (SMMT) said the industry is investing billions to reduce emissions and the latest diesel cars are the cleanest in history.
According to its figures, emissions of nitrogen oxides have reduced by 84% since 2000, while new filter technology can capture 99% of all soot particles from diesel engines.