Fiat denied a report that it plans to slash 18,000 jobs by closing or scaling down 10 factories in Europe in a possible takeover of Germany's Opel.

"The Fiat Group clearly states that it is not information generated by Fiat and does not form part of any plan prepared by Fiat," the company said in a statement released late Tuesday.

Citing a sensitive internal document, the Germany daily Frankfurter Allgemeine Zeitung (FAZ) said Fiat would want to cut 18,000 jobs, closing or scaling down 10 factories in Europe if it reaches a deal with GM.

The document was reportedly titled 'Project Football' and dated April 3. It said the jobs would be cut from the 108,000 total at Opel, GM Europe and Fiat, or 16.6 per cent, if a deal is reached. British Vauxhall assembly lines in Luton and Ellesmere Port, as well as the Opel factory in Antwerp, Belgium, would be among those shut down, along with Fiat factories in Pomigliano, near Naples, and in Termini Imerese, Sicily.

Three Opel plants producing gearboxes - Bochum, Kaiserslautern and Ruesselsheim, Germany - would also be partially shut down, FAZ said. Fiat boss Sergio Marchionne on Monday presented his plan to take over Opel, a GM subsidiary, to sceptical German government ministers.

He said his group had no plans to close any of Opel's four factories in Germany, while adding in an interview with the German daily Bild: "The workforce of course has to be reduced" in order to boost productivity.

In late March, Marchionne, who rescued Fiat from the brink of collapse in a few years without massive job cuts, did not rule out closing factories in Italy, where the group is a national industrial icon and the country's top private employer.

"I cannot give a reply, either positive or negative," he told a journalist when asked whether he would give a pledge that no factories would close in Italy.