The investment, first revealed by PrintWeek earlier this month, will allow the two sites to print a 128pp Daily Mail and a 160pp The Mail on Sunday in full colour by 2008.
John Bird, managing director of Associated's London print site Harmsworth Quays, said: "We believe that the new Cerutti satellite cylinders offer better registration and printing quality."
He described the decision to go with Cerutti for the presses as "tough". "We have a very good business relationship with KBA... and we will continue to work closely with them," he said.
The 80m investment at the Didcot site will be complemented by a 16m spend at Harmsworth Quays to upgrade its eight Flexo-Courier presses to print full-colour.
Didcot's Cerutti presses will incorporate a quarter-fold feature that will allow the site to produce smaller commercial products throughout the day.
A reel store with automatic reel loading and capacity for up to 800 reels will form part of the plant, which will be built on a 12-acre brownfield site in the Oxfordshire town.
Harmsworth Quays production director Christine Klafkowska will head up the new plant. Associated has said that some staff will move from London to the new site, but most staff will be recruited locally.
Lord Rothermere, Associated Newspapers chairman, said: "This is further evidence of our commitment to the long-term future of our newspapers."
The deal is Cerutti's first in the newspaper sector in the UK. The Italian firm has built the presses for Polestar's new site in Sheffield, while Italian titles such as La Repubblica, Corriere della Sera and La Stampa use the firm's machines.
Story by Josh Brooks
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