Already available to order in selected markets, with first deliveries from September, the new engines form part of a package of additions for the carmaker’s compact models.

The CLA 200 CDI will use a new 2.2-litre engine, replacing the 1.8-litre diesel used to date. The result is a large cut in running costs, with fuel economy of 68.9mpg and CO2 emissions of 107g/km, or 70.6mpg and 104g/km for the 7G-DCT dual-clutch automatic, compared to 62.8mpg and 118g/km for manual and automatic gearboxes with the old engine.

In the GLA-Class range, the new 180 CDI variant introduces the same 1.5-litre Renault-Nissan sourced diesel used in the A-Class as an entry-level front-wheel drive model. This 109bhp engine returns 72.4mpg and emits 103g/km with the 7G-DCT gearbox, or 70.6mpg and 105g/km with the manual.

4MATIC four-wheel drive will also be introduced on the CLA 200 CDI, CLA 220 CDI and A220.

Ola Källenius, member of the Mercedes-Benz Cars divisional board responsible for sales, said: ‘Our compact models have proved exceptionally popular with customers and provide younger customers in particular with an attractive means of gaining entry into the brand. This is reflected in the capture rate enjoyed by the compact car family.’