France's national rail company SNCF said on Tuesday it had ordered 2,000 trains for an expanded regional network that are too wide for many station platforms, entailing costly repairs.
A spokesman for the RFF national rail operator confirmed the error, first reported by satirical weekly Canard Enchaine in its Wednesday edition.
"We discovered the problem a bit late, we recognize that and we accept responsibility on that score," Christophe Piednoel told France Info radio.
Construction work has already begun to reconfigure station platforms to give the new trains room to pass through, but hundreds more remain to be fixed, he added.
The mix-up arose when the RFF transmitted faulty dimensions for its train platforms to the SNCF, which was in charge of ordering trains as part of a broad modernisation effort, the Canard Enchaine reported.
The RFF only gave the dimensions of platforms built less than 30 years ago, but most of France's 1,200 platforms were built more than 50 years ago. Repair work has already cost 80 million euros ($110 million).
Transport Minister Frederic Cuvillier blamed an "absurd rail system" for the problem, referring to changes made by a previous government in 1997. "When you separate the rail operator (RFF) from the user, SNCF, it doesn't work," he told BFMTV.