Audi is about to reveal a facelifted version of its A8 luxury car with lower emissions.

Speaking to BusinessCar, UK managing director Martin Sander said: “[It will be] mainly cosmetic, a larger boot, which is important in the segment, and lower CO2 across the range. [The styling changes will be] mild but clearly visible.”

He confirmed that the model will be revealed around the fourth quarter, suggesting it could make its debut at September’s Frankfurt motor show, with an on-sale date of early 2014.

Sander also hinted that the firm’s best-selling, lower medium A3 was in for some lower-CO2 engines in the near future: “The A3 is already 99g/km. Next year we’re going to have both a diesel and a petrol engine below 99g/km.”

Talking about the current diesel, he added: “If we have 99g/km right now, you can clearly expect that in the not-too-distant future there will be a lower number.”

An Audi spokesman added that the firm has “the broadest model range it’s ever had” for fleets.