Switzerland's Administrative Court has ruled that each new double-decker train must have at least one wheelchair ramp.
In its ruling announced on Thursday, the court said the ramp must also provide access to an area for wheelchairs and an accessible toilet.
The trains, which will come into full service on December 9, were designed so people with a disability can enter or leave from any door independently. However, when the trains entered a test phase, it was found that wheelchair users could not get in or out without assistance because the ramps were too steep.
The umbrella organisation representing disabled groups, Inclusion Handicapexternal link, said it was disappointed by the court decision allowing only one accessible ramp per train.
In a statement it said that people with a disability are guaranteed equal access by law, but the ruling meant this was not the case.
Inclusion Handicap will consider appealing the decision to the Supreme Court.