Troubled Italian food giant Parmalat has sued its former auditors Deloitte & Touche and Grant Thornton for at least US$10bn for allegedly failing to properly audit the company and therefore prevent a massive accounting scandal at the company.

Parmalat said it was suing Deloitte Touche Tohmatsu and Grant Thornton International, and their Italian and US affiliates, in the lawsuit that was filed this week in the US, reported Reuters.

“Because the defendants failed to properly audit Parmalat and in many cases with defendants’ active participation, something in the order of $10bn has gone out the door and been stolen, squandered or wasted by Parmalat insiders,” the company was quoted by Reuters as saying.

Parmalat’s new management claimed auditors from Grant Thornton had been conspiring with the Italian company’s former management, while auditors at Deloitte had repeatedly failed to spot the warning signs.

Both Deloitte and Grant Thornton said the lawsuit was unjustified.

Late last year billions of euros were found to be missing from Parmalat’s accounts. Several former executives of the company, including founder Calisto Tanzi, are facing fraud charges in Italy.