Sadiq Khan has announced that he will close 20 kilometres of roads in the capital city as part of a car-free day.
Activists are responding to an inquest into whether the death of a nine-year-old girl was linked to air pollution.
One in three Britons have inhaled toxic air in the country's busy city centres, it has emerged.
Alastair Harper, Head of Advocacy at Unicef UK has said that one in three children are living in areas that would be classed as having “toxic levels of air pollution”.
The mother of a nine-year-old whose death has been linked to high pollution levels has criticised London councils for continuing to build schools in high-traffic areas.
The most polluting log burners and stoves will be banned as part of a strategy to tackle air pollution, the Environment Secretary has announced.
Parents are also being urged to walk their children to school over taking them in a car.
New legislation will be implemented as part of efforts to cut harmful dirty air.
Baroness Jenny Jones says the Government needs to invest in public transport so people can get around without cars
Figures have been reported which claim pollution causes almost 40,000 premature deaths a year in the UK, but a respiratory physician has said the figure is wrong
The bus runs entirely on electricity and is named Scossa, which means shock. It made its first trip on Wednesday and seven months of tests
Campaigner Areeba Hamid slams the UK government following statue protest