Mercedes will launch its ultra-clean Bluetec diesel engines in Europe in December - but it hasn't been confirmed for the UK yet.
The E-Class will be the first to get the engines, but they will also be fitted to the C-Class from 2009, with a C250 capable of 57.7mpg and a C300 hybrid returning 61.4mpg.
The technology was first launched in the US in the E-Class a year ago, and it now accounts for 20% of the car's sales. The R-Class, GL-Class and ML class will get the engines there soon.
Dermot Kelly, managing director of Mercedes Car Group UK, said: 'Bluetec is still not confirmed for the UK. There's a chance it might not happen, but I don't think that's the case. I believe it's a case of when, not if.'
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