I'd imagine so.
The Micra 1.2 would be closer to the Mirage 1.2, which on the same route turned in 56 mpg US = 4.2 L/100km = 67 mpg Imp with basic ecodriving techniques (plus manual stop/start at lights, as I did with the Micra 1.6).
The Mirage has the city advantage of much lighter weight:
- 895 kg (1973 lbs) manual Mirage, vs...
- 1044 kg (2302 lbs) for our manual Micra, which is at the portly end of its class.