Interest in Ford’s lowest emission Focus has been so great that executives have admitted they have underestimated the annual volume, and are looking for more capacity to build the car.

Ford believed when it launched the 1.6 TDCi Econetic, with emissions of 115g/km of CO2 and fuel economy of 65.6mpg that it could sell around 3,000 units a year in the UK.

Despite the fact that the car has been slow to market, with delays in production and delivery meaning the first models are only now being delivered to customers, all 3,000 have already been accounted for, with fleets among the main customers.

Speaking at the launch of the Ford Kuga, a Ford spokesman said: “Because the standard Focus 1.6 TDCi is 119g/km, and so below that all important 120g/km threshold, we believed there would be interest for the lower Econetic version, but not in the great numbers we are seeing.”

Ford believes that the surge in customer enquiries for Focus models with the Econetic badge shows the value of having a bespoke environmentally friendly brand.

“Changes from the standard Focus are slight,” said the spokesman.

“They include low viscosity oil and engine remapping, but it goes to show the importance of people wanting to show they are doing their bit for the environment.”

Ford said it should have no problems ramping up production.