A mobile terminal device (ME) determines whether it is located in the local radio area (HFB) of the network (MN) or in another radio area (FB2) and the determined radio area (HFB, FB2) is indicated to an application (APPL) of the network (MN). The application (APPL) is used to control a communication request (KV) addressed to the mobile terminal device (ME) by another network (FN) either to its local radio area (HFB) or to forward it to the other radio area (FB2) or the communication request (KV) is informed that the terminal device (ME) is not located in the local radio area (HFB). The invention allows communication requests coming in on the network (MN) to be directly switched to the local radio area (HFB) using the application (APPL) or to be directly forwarded to the mobile radio address in the mobile radio network of which the mobile terminal device (ME) is located, thereby avoiding or substantially reducing roaming or forwarding of communication requests from the local radio area (HFB) to another radio area and thereby achieving an economical operation of mobile telephone terminal devices (ME) with local radio area (HFB).