Deutsche Bahn, Germany's state-owned railway operator, will rent out a network of fiber-optic cables it has laid along its rails to telecoms firms to provide a speedy internet service to companies and homes in remote areas, it said on Tuesday.

The company has built the fiber-optic network over several years, primarily for its own communications and signaling, but also with an eye to renting out the infrastructure at a time when it faces a costly task to upgrade its national railways.

Germany's internet infrastructure is lacking behind other industrialized countries, especially in rural areas.

Deutsche Bahn, which has created a new subsidiary to sell the service, said its 18,000 km fiber-optic network would reach the most remote train stations. It also owns land next to its railways where mobile network antennas could be built, it added.

According to an internal document seen by Reuters, Deutsche Bahn has already seen significant interest this year from potential clients who want to use its fiber-optic network.

That initial interest, if firmed up, would lead to deals worth €2.4 million, the document said. By 2023, the new service could yield revenues of more than €42 million, with profits of €22 million, it added.