Priced from £35,130 for a 2.0-litre diesel model and £40,600 for a petrol version, the third generation X1 is some two inches longer at 4.5 metres and almost an inch wider.
Boot space on the combustion engine versions is now 540 litres, expanding to a maximum of 1,600 litres.
Prices for the plug-in hybrids and the all-electric iX1 are still to be revealed, but BMW has announced that the iX1’s motor develops the equivalent of 313 horsepower, can accelerate from 0 to 62mph in 5.7 seconds with a maximum of 112mph.
With a 64.7kWh battery, it has a fully charged range of up to 272 miles. A full charge takes 6.5 hours or three hours 45 minutes from a fast charger, while an 80 percent recharge is possible in 29 minutes.
A 10-minute top-up gives the car an extra 75 miles range.
The plug-in hybrid versions have a three-cylinder engine developing either 245hp or 326hp which in the case of the latter elicits a 0 to 62mph sprint time that matches the iX1 while on paper fuel economy is rated at 353.1mpg with emissions of 17g/km.
Performance figures for the xDrive23 petrol model are an acceleration time of 7.1 seconds with a top speed of 145mph and best fuel return of 43.5mpg and emissions of 146g/km while the diesel X1 sDrive18 is rated at 8.9 seconds 0 to 62mph, a maximum of 130mph and fuel consumption of 57.7mpg with a CO2 figure of 129g/km.
All versions of the new X1 come with BMW’s latest architecture, which sees a large front grille flanked by LED headlights as standard.
Inside, the cars feature BMW’s Curved Display layout with two display screens behind a single panel and use the Bavarian car maker’s latest computer operating system for onboard technology.
At launch five trim levels - Sport Premier, xLine Premier, xLine Premier Pro, M Sport Premier, M Sport Premier Pro – will be available with the PHEV and iX1 models joining the line up later.