Abstract: A telecommunications system and method for performing a handover between the fixed (wireline) network and a mobile network during a call placed to or from a dual mode device, without any interruption in the voice or data connection. Therefore, for calls initiated in the fixed network, once the subscriber leaves the coverage area for the fixed mode of the dual mode device, the call continues as normal by transferring the call to the mobile network. Similarly, for calls initiated in the mobile network, once the subscriber moves back into the fixed mode coverage area, the call can be transferred to the fixed network in order to provide a lower rate to the subscriber, without any service interruption.