Paris, France, will have a Low Emission Zone from 1st July 2015, trucks and buses must be Euro 1.
From 1st July 2016 all vehicles must be Euro 1. Between 2017 and 2020, Euro 2, 3 and 4 will gradually be regulated. Investigations into limited traffic zones (almost pedestrian areas) and ultra-low emission zones in certain areas and roads could be experimented with in 2016.
For more details, see our Paris page.