The Mayor said the level of dangerous particulates in the air has been reduced by 15% because of action on encouraging clean vehicles, walking and cycling. He also said he has introduced a plan to bring in an Ultra Low Emission Zone for vehicles in London by 2020.
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Turning cloudy and windy but feeling mild at the weekend.
The Ukip leader also says his children his hid in a graveyard and were brought back by police.
Here's a borough-by-borough breakdown of the official figures.