The recall has affected around 8,50,000 vehicles mainly sold in Europe. Audi followed on July 21 with its own recall to update the software in Euro 5 and Euro 6 engines.
The software update on the diesel engines will take around an hour, and it will be carried out free of charge.
Audi spokesman Udo Rügheimer said the move was to try and restore confidence in diesel and ensure it has a future.
More than 200 employees of the carmakers formed 60 working groups covering "all areas of auto development, petrol and diesel engines, brakes, transmissions and gearboxes.as well as choice of suppliers and prices for parts", an excerpt of the report read.
With the recall action in close consultation with Germany's Federal Motor Transport Authority, the company intends to reduce overall emissions, especially in urban areas, according to its statement, as well as to maintain the future viability of diesel engines.
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Audi is offering its customers in Europe and other markets* a retrofit program for cars with EU5 and EU6 diesel engines. Cities such as Paris, Madrid and Mexico City are looking into banning the models because of air pollution concerns.
The German automaker said the recall affects vehicles with six- and eight-cylinder diesel engines and will involve updating the cars' software at no cost to the vehicles' owners.
Volvo said it would ditch diesel from 2019 in favour of plug-in hybrids while the United Kingdom government is pressing ahead with clean air zones in cities, parking surcharges for diesels and potential pay-per-mile road pricing.
Since 2006, there had also been "innumerable meetings" about diesel exhaust processing created to reduce emissions of harmful nitrogen oxides (NOx).
He added: "What Audi and Mercedes have announced is just the tip of the iceberg".
The report shows that the companies have been secretly meeting in various working groups since the 1990s, where they agreed on various technologies, costs, suppliers and even how to work on emissions from diesel engines.