Rail freight services have been suspended in wide areas of western Japan following record-high rainfall in the region this month.
Japan Freight Railway Company President Koichi Shingai told reporters that full recovery will take more than one month.
Shingai said the disaster severely damaged rail services, but that JR Freight will work with JR West and JR Shikoku to restore them as soon as possible.
He added that the disruption has affected supplies of agricultural commodities and paper products.
The freight company last week began alternative services by truck and cargo ship that cover only about 13 to 14 percent of normal rail transport volume.
The firm plans to use more trucks and is considering roundabout routes, but did not say when it would start using such routes.