A telecommunications apparatus (10) is provided which comprises a processing system (12), a cellular-network radio transceiver (14), a first radio module (20a) and a smart card (18). The smart card (16) comprises a microcontroller (17), an electrical interface (24) and a second radio module (20b). The cellular-network radio transceiver (14) and the first radio module (20a) are connected to the processing system (12) by one or more electrical connections (22). The smart card (18) is coupled to the cellular-network radio transceiver (14) through the electrical interface (24) and the processing system (12) is arranged to use a radio communication link (26) between the first radio module (20a) and the second radio module (20b) to communicate data with the microcontroller (17) of the smart card (18). The smart card (16) is configured to interrupt the processing system (12) by sending data over the radio communication link (26).