Extensive revisions to the Lexus Hybrid Drive system have helped bring down the RX 450h's CO2 emissions to 148 g/km - a figure that is significantly lower than any other competitor model in the premium crossover class, including the best-performing diesels.

As well as being cleaner, the new RX 450h is also more fuel-efficient than the RX 400h, the model which introduced hybrid power to the premium market. Combined cycle consumption is improved by 28 per cent to 19.05 km/l.

The RX 450h is powered by a series/parallel hybrid system employing a highly efficient 3.5-litre V6 petrol engine and two powerful electric motors working in tandem to provide an 'intelligent' four-wheel drive capability. Total power output is 295 bhp, enabling a top speed of 200 km/h and zero-to-hundred acceleration in 7.8 seconds.

Full details of the new Lexus RX 450h will be released at the Geneva motor show next week.