A method of operating a wireless local area network, WLAN, access point device , located at a user premises, to control access by at least one mobile device to a voice service provided by a cellular network and accessible via a cellular network gateway located at a logical edge of the cellular network and connected to a wide area network , the WLAN access point having a WLAN interface for communication with the at least one mobile device via a WLAN wireless link , and a wide area network interface for communication with the cellular network gateway and for communicating with the wide area network via a wide area network link, and the at least one mobile device having a non-cellular WLAN interface for communication with the WLAN access point and a cellular network interface , the method being performed by the WLAN access point and comprising: determining whether current network conditions on at least the WLAN wireless link , the wide area network link and a data path to the cellular network gateway can support a predetermined set of voice service requirements (s9) by: determining performance metrics for the WLAN and performance metrics for the link to the wide area network (s21); establishing a communication link to the cellular network gateway and determining performance metrics for the established link (s21); comparing a subset of the determined performance metrics against a set of thresholds required for the voice service (s25); receiving a request from the mobile device to the cellular gateway for the voice service (s5); and if the determination is that the voice service can be supported by the current network conditions to the cellular network gateway , allowing a connection to the voice service to be established by the mobile device (s13); if the determination is that the voice service cannot be supported by the current network conditions, blocking the voice service request (s15) so that in response to the block, the mobile device will connect to the voice service via the cellular network interface and cellular network (s17). determining whether current network conditions on at least the WLAN wireless link , the wide area network link and a data path to the cellular network gateway can support a predetermined set of voice service requirements (s9) by: determining performance metrics for the WLAN and performance metrics for the link to the wide area network (s21); establishing a communication link to the cellular network gateway and determining performance metrics for the established link (s21); comparing a subset of the determined performance metrics against a set of thresholds required for the voice service (s25); determining performance metrics for the WLAN and performance metrics for the link to the wide area network (s21); establishing a communication link to the cellular network gateway and determining performance metrics for the established link (s21); comparing a subset of the determined performance metrics against a set of thresholds required for the voice service (s25); receiving a request from the mobile device to the cellular gateway for the voice service (s5); and if the determination is that the voice service can be supported by the current network conditions to the cellular network gateway , allowing a connection to the voice service to be established by the mobile device (s13); if the determination is that the voice service cannot be supported by the current network conditions, blocking the voice service request (s15) so that in response to the block, the mobile device will connect to the voice service via the cellular network interface and cellular network (s17). <EOS>