The invention concerns a method of providing a Push-to-Talk (=PTT) service within one or more telecommunication networks (1, 2, 3, 4) by means of a gateway-server (5) which sets up a virtual connection per PTT connection. The virtual connection provides information about the participating terminals (10, 20, 30, 40) of the PTT connection, the service type to reach each terminal (10, 20, 30, 40), and the connection status of each terminal (10, 20, 30, 40). Thus, the gateway-server (5) is capable of providing the PTT service within and/or across different telecommunication networks comprising radio access telecommunication networks (1), fixed wire-line telecommunication networks (2), circuit-switched telecommunication networks (3), and packet-switched telecommunication networks (4).