As political pressure grows over declining air quality in the world's big cities, London has become a test bed for policy among global capitals. The FT's Daniel Garrahan reports asks whether the transition to electric vehicles is being made quickly enough.<br /><br />► Subscribe to FT.com here: http://bit.ly/2GakujT<br /><br />► Subscribe to the Financial Times on YouTube: http://bit.ly/FTimeSubs<br /><br />For more video content from the Financial Times, visit http://www.FT.com/video<br /><br />Twitter https://twitter.com/ftvideo<br />Facebook https://www.facebook.com/financialtimes
