The Turin-Lyon high-speed rail link represents a project "very concerning for the future balance of public finances". This time, it is not those who have opposed the high-speed rail project between the Piedmontese capital and the capital of Rhône-Alpes for years who are saying so, but the French Court of Auditors, which, in a report submitted to Prime Minister Manuel Valls, casts a shadow over the economic feasibility of the enormous project.

Il primo ministro francese Manuel Valls in visita al cantiere della Tav Torino Lione ©JEAN-PHILIPPE KSIAZEK/AFP/Getty Images

But Paris presses ahead with the high-speed rail link

The document, published at the end of August, concerns in particular the French transport infrastructure financing agency (Afitf). According to the analysis by the French auditors, which also takes into account another project co-financed by the agency, "these are works that appear to be largely beyond the economic reach of the agency. Not only with regard to 2019, but also for the years that follow."

The Court of Auditors' verdict on the high-speed rail link therefore seems unequivocal. Translated into more concrete terms, "if the state decides to continue its commitment to the projects in question, for the period between 2017 and 2019 alone it will have to allocate between 1.6 and 4.7 billion more than the resources envisaged so far". The French government, however, responded to the report immediately, declaring that the finances are in order and that the decisions on the project will not be revisited.

No Tav Val di Susa — A demonstration against the high-speed rail link in Val di Susa ©Stefano Guidi/Corbis via Getty Images

The cost of the high-speed rail link estimated at 26.1 billion euros

Yet this is not the first time the Paris Court of Auditors has sounded the alarm over the high-speed rail link. As far back as 2012, it had explained how the costs of the project had risen steeply, increasing from an initial forecast of 12 billion euros (in 2002) to an estimate of 26.1 billion. The Italian and French governments have repeatedly stressed that part of the works is financed by the European Union. But Brussels will be able to cover at most 40 per cent of the cross-border section alone — that is, only the twin-bore tunnel (57 kilometres long) that is intended to connect the two countries. The remainder will fall entirely to the latter.

The cost of the two tunnels alone is currently estimated at 8.6 billion euros: assuming, therefore, that 40 per cent is guaranteed by the EU, France will bear 25 per cent (equivalent to 2.2 billion). Italy, meanwhile, will have to pay the remaining 35 per cent, that is, more than 3 billion.

French Court of Auditors rejects the Turin-Lyon high-speed rail link