A communications assembly including a first mobile station communicatively coupled to a public mobile radio network, a second mobile station communicatively coupled to a private mobile radio network, and a communications interface module configured to provide a communication conduit between the first mobile station and second mobile station, for routing: a communication originating from the first mobile station through the communications interface module for transmission over the private mobile radio network via the second mobile station, and a communication initiated at the communications interface module for transmission over the public mobile radio network via the first mobile station device.