The Green Party has published this picture, claiming that is shows "why we need a very low emission zone for central London ASAP, not in 2020".
It is a map of nitrogen dioxide (NO2) pollution in the congestion charging zone, put together by Assembly Member Jenny Jones.
It is based on NO2 emissions modelling carried out by Kings College London, not on actual readings.
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A Labour MP has angered Ed Miliband after she tweeted a picture of a house draped with England flags with the words "Image from Rochester."
The bizarre combination was filmed as it raced along Whitechapel High Street in East London.
The mayor claims America's Inland Revenue Service has hit him with a bill for unpaid tax on the sale of his home.