Yesterday morning the European Parliament's Environment Committee voted for strong and comprehensive measures to combat air pollution, strengthening current laws limiting emissions on harmful pollutants for Member States.
At the same time, the findings from a new report by City Hall were breaking in London. The death toll from air pollution in our capital is hitting nearly 10,000 a year - twice as high as previously thought.
But the report also revealed a much overlooked and inconvenient truth - particularly to those on the Tory backbenches - that nearly half of the negative health effects caused by air pollution come from outside of London and the UK, including agricultural, diesel and industrial emissions blown across the channel.
This is why the vote in the European Parliament today was so crucial.
MEPs backed strict and binding air quality targets for 2020, 2025 and 2030 to ensure all EU government's take action to reduce harmful emissions were agreed, particularly in cities and urban areas where the problem is so acute.
We pushed for amendments giving more powers to local and regional authorities.
We voted for obligations that force governments to mitigate the effects of emissions on children, the elderly and those living in poor areas
We agreed that more must be done to force car manufacturers to test their engines on roads and in traffic, not in ideal-laboratory conditions where manufactures can play the system - some diesel cars spew out 22 times more NO2 than the legal limit.
And we also secured a victory for democracy, putting provisions in place that allow members of the public and NGOs to have access to administrative or judicial means to challenge governments when they fail to act.
Our action puts the conduct of Boris Johnson and David Cameron into sharp focus.
The government had to be dragged through the courts to take action on the existing limits, while The Mayor has wasted his seven years in office. Oxford Street broke annual NO2 limits in just four days this January, proof that his plans for a new ultra low emission zone (ULEZ) in London for 2020 are too little and too late.
Telling Londoners to stay indoors during smog episodes speaks volumes about the Boris Johnson's negligence.
The European Parliament's Environment Committee has taken a big step towards fundamentally changing the rules of the game when it comes to tackling air pollution.
The agreed text must now be voted on by the entire Parliament before negotiations begin with other Member States.
The UK government and Mayor must follow our lead and take effective action to tackle air pollution once and for all.