EU set the manufacturers a fairly challenging target for 2021
http://ec.europa.eu/clima/policies/transport/vehicles/cars_en.
"By 2021, phased in from 2020, the fleet average to be achieved by all new cars is 95 grams of CO2 per kilometre."
It's unclear to me whether that average is based on sales or the product range but manufacturers will need to have a substantial number of vehicles below that target. It's no so difficult with diesel but they need to tighten up on the requirements for real life measurement of emissions other than CO2 so that manufacturers see the urgency to develop the alternative technologies.
To me, an improved Honda IMA setup with a bigger motor/generator (a 3 cylinder engine makes room for this) and a reasonable capacity lithium battery pack would work well in the Mk 3 Jazz.