Campaigners are urging the Government to phase out diesel vehicles in order to improve air quality

<<VOICED: One of the country's leading clean-air campaigners has called on the government to begin phasing out diesel vehicles, after latest measurements revealed many areas of the UK regularly breach international guildelines on acceptable levels of pollution. It comes as the Government prepares to publish a revised action plan to improve air quality, after the courts ruled the current plan was inadequate. Sky correspondent Mark White has this report. >> on April 15, 2017 in London, United Kingdom.