Ford will offer “ultra fuel-efficient” versions of the Focus and Fiesta in Europe next year as part of a green-technology strategy.

The ECOnetic Focus and Fiesta, scheduled to debut at the Frankfurt auto show next week, will be powered by a new version of Ford’s 1.6L Duratorq diesel engine. Ford says the Focus will achieve 89 g/km carbon-dioxide emission levels, while the Fiesta will produce just 87 g/km CO2.

The Focus is rated at 83.1 mpg (3.4 L/100 km), making it the most fuel-efficient non-hybrid C-segment car in Europe, while the Fiesta will achieve 85.6 mpg (3.3 L/100 km), Ford says.

The expansion of ECOnetic technology will help Ford achieve its goal of a 30% reduction in CO2 emissions between 2006 and 2020, the auto maker says.

ECOnetic technologies include features such as auto start/stop, regenerative braking and active grille shutters.

Ford says about half the cars it sells in the second half of 2012 in Europe will carry ECOnetic technologies, increasing to an expected two-thirds by mid-2013.