Nissan luxury brand Infiniti will be the first premium brand to offer both diesel and hybrid alternatives of the same model when the petrol-electric version arrives in the UK within 18 months.

Infiniti recently launched in the UK but only with a range of 3.5-litre petrol engines across the upper medium G saloon, coupe and convertible range, and the off-roader EX and FX models, the latter also coming with a 5.0-litre V8 alternative. None of its models currently get below 246g/km of CO2 or better 26.9mpg, making them fleet-unfriendly.

But a large-capacity diesel version of the BMW 5-series-rivalling M model, potentially a 3.0-litre unit, should come with the new addition by the end of next year, around six months ahead of the hybrid. Though Infiniti is not yet quoting figures, it has confirmed that the hybrid version will be the brand’s cleanest and most economical car.

At present, Lexus has a range of hybrid models, but none that also offer a diesel alternative, while BMW and Mercedes have developed hybrid version of the 7-series and S-class respectively, though the German brands aren’t bringing those models to the UK.

Toyota will be the first brand to offer diesel and hybrid versions of the same model by the end of the next year when it launches its Auris hybrid.