An additional $60 million reduction is planned in other long-distance and operator services, the company added.

Numbers beginning with 01 are for operator services.

The rivals also are expected to offer operator service this year for the first time.

Overseas callers to North Korea will usually need to go through the international operator service on +850 2 18111.

An operator service through a free telephone number is also available 24 hours a day.

However, many operator services are now automated with minimum human intervention.

For callers, then, the issues are twofold: First, how do you know if the call is being carried by an alternative operator service?

If it is a company you haven't heard of, chances are your call will be carried by an alternative operator service.

The caller may still be frustrated, however, if the phone has been wired to route calls only to an alternative operator service.

Industry representatives say that alternative operator services are making other adjustments.