Both the Mini One and the Mini Cooper D arrive here in April after going on display at the Geneva Motor Show next month.

The entry-level One comes with a perky 1.4-litre petrol engine, which puts out 94bhp, and the Cooper D combines performance and fuel economy from the all new 1.6-litre turbo-diesel, which develops 110bhp.

The Mini One shows a big improvement in both fuel consumption and emission levels over the outgoing model. Figures from the company claim a 5.7l/100km return from the new engine compared to 6.8l/100km from the predecessor (an efficiency increase of 15%) with emission levels down from 164g/km to 138g/km.

The compact engine is constructed from light aluminium and peak torque of 140Nm comes in at 4,000rpm. The sprint to 100km takes 11 seconds and the top speed is 185km/h.

The diesel power plant brings in equally encouraging news. BMW say that this will be the most fuelefficient and cleanest Mini ever built.

In comparison to the outgoing Mini One D, the combined fuel consumption of 4.8l/100km is apparently reduced to 4.4l/100km.

Under normal conditions, peak torque of 240Nm is reached between 1,750rpm and 2,000rpm.

However, deploying the engine's overboost gives an additional 20Nm of torque, which gives the driver 260Nm of torque at 2,000rpm . . . this is identical to that produced by the new Mini Cooper S. The 0-100km sprint takes less than 10 seconds and the top speed is 195km/h.

When it goes on sale the Mini One will be priced at 21,350 and the Cooper D will be priced at 26,400.

Both models have the same new body shape as the Mini Cooper and Cooper S models launched last year.

Both cars also come with a sixspeed manual transmission and the Mini One will have the option of a sixspeed automatic transmission.