A new "carbon map" released today shows businesses in Newry are the lowest emitters in the UK.
The new league table found business accounts for more than half of carbon emissions in some urban areas and highlights the areas in which businesses are emitting well over the national average of 40 per cent of CO2.
In Leicester, Norwich and Sheffield, businesses generated 55 per cent of carbon emissions - the highest percentage. In Cambridge and Reading the figures are 53 per cent and 50 per cent respectively.
Businesses in Newry, Northern Ireland, emitted the lowest proportion - just 26 per cent of the city's CO2 emissions.
The Carbon Trust created the new map to spur businesses to take action on climate change. Of the 33 towns and cities assessed in 2004, Greater London emerged as the area with the highest overall volume of CO2 emissions from industry, at 50,754,000 tonnes.
Tom Delay, chief executive of the Carbon Trust, said: "Business has a critical role to play in tackling climate change ... and poor energy efficiency costs business an estimated stg£2 billion annually.
"Implementing straightforward energy saving measures in the workplace could reduce energy bills by up to 20 per cent, enhance their reputation and drastically cut their carbon footprint."
The Carbon Trust is an independent company funded by the British government to help the move to a low carbon economy.