The invention relates to a radio-communication system for Push-to-Talk applications, comprising: a narrow-band PMR-technology terminal capable of connecting, via a radio-electric interface, to a narrow-band network infrastructure for accessing, via a PTT server, a set of narrow-band PTT resources or applications; and a wide-band-technology terminal capable of connecting, via a radio-electric interface, to an IP-WAN network for accessing, via a server, a set of wide-band PTT resources or applications, wherein said terminal comprises a client PTT application on the IP-WAN network configured to establish an IP connection between the terminal and a PTT server over the IP-WAN via an interface, such that said terminal can access the narrow-band PTT resources or applications and establish a communication channel with the terminal.
