Japan Post may have its general cargo vehicle license revoked, the transport ministry said Wednesday, following revelations of the company's widespread failures in conducting mandatory alcohol and health checks for its drivers.

The unprecedented move would be the heaviest administrative penalty available under the motor truck transportation business law, which stipulates that business operators must conduct sobriety checks for their drivers before and after work.

If the revocation goes ahead, Japan Post would be barred from reapplying for a new license for five years, affecting around 2,500 trucks and one-box vans used by post offices nationwide.

While the company's 32,000 mini vehicles would not be affected by the measure, as they are not covered by the license, the ministry is also reportedly considering barring Japan Post from using such vehicles.

A formal hearing with the company will be held on June 18 at the Kanto District Transport Bureau in Yokohama.

Disruptions to the company’s transport services — including parcel deliveries — are seen as inevitable, and the company is reportedly considering outsourcing its operations to mitigate the impact.

The safety violations first came to light in January, when it was discovered that a post office in Hyogo Prefecture had for years failed to properly check drivers' sobriety, fatigue level and quantity of sleep.

In April, Japan Post disclosed that improper checks had occurred at 75% of its 3,188 delivery offices nationwide. In response, the transport ministry launched a special audit on April 25 under the motor truck transportation business law and began on-site inspections at facilities such as Takanawa Post Office in Tokyo’s Minato ward and others across the country. The ministry has prioritized inspecting post offices that operate trucks and one-box vehicles, which pose higher accident risks if driven while drunk.

The audit revealed numerous instances of missed checks and falsified records in the Kanto region alone, far surpassing the threshold for license revocation. A senior ministry official said the violations “undermine the very foundation of transport safety.”

Japan Post issued a statement acknowledging the severity of the situation, saying, "We deeply regret this matter and apologize for any inconvenience it may cause to our customers and other concerned parties."

A transport ministry official said they will provide support to Japan Post to lessen the impact on its distribution network should its license be revoked.