For the first time there were two Kia models, the Ceed and the Sportage, in the company’s best-selling charts. The Ceed rose 51 places to seventh in terms of sales volume, while the Sportage rose from 10th place last year to eighth place this year. 

However, it was the German brands who continued to dominate the top spots, with the Audi A3 moving up one place to be 2013’s most popular model. This was followed by the Volkswagen Passat, which dropped down one place from its number one position in 2012 to finish second this year. 

Hard on their heels came two cars from Vauxhall, with the Insignia in third position, up one place on last year, and the Astra in fourth place, up from 13th position in 2012.

Models that dropped out of the Fleet Alliance top ten included the Ford Mondeo, which fell from fifth place in 2012 to 33rd this year; the BMW 5 Series which fell from seventh place to 11th; and the Skoda Octavia down from ninth place last year to 18th this year. 

Fleet Alliance also reports a continued drop in CO2 emissions across the fleet, with an all-time low of 123g/km per vehicle on average, compared with 125g/km in 2012. Some 61% of the Fleet Alliance fleet now emits less than 130g/km, compared with 53% last year. 

Official figures from the Society of Motor Manufacturers and Traders put the average carbon emission for all new vehicles ordered in the UK last year at 133g/km, substantially above the Fleet Alliance average. 

The greenest models, however, are not necessarily the most popular. 

The lowest carbon-emitting car on the Fleet Alliance fleet is the Toyota Auris with average emissions of just 91g/km, but it is only the 32nd most popular in terms of number ordered. Second place goes to the Citroen DS3 with 97g/km, but it is only the 33rd most popular model. 

The Fleet Alliance top 10 cleanest models are as follows: