Italy’s government failed to agree on Saturday on a law that would make it easier and less costly to revoke concessions to operate motorways, a sign of division among the ruling parties on how to handle the aftermath of a fatal road bridge collapse last year. A government minister who did not want to be named said after a five-hour cabinet meeting that the government had provisionally approved a document, but measures still needed to be agreed on before it becomes definitive. It also considerably reduces the amounts the government must pay to a toll road company if a concession is revoked due to shortcomings on the part of the operator.