A method performed by a communication device (103a-c) outside a coverage area of a cellular communication network, wherein the communication device (103a-c) is configured to perform a device to device communication with a plurality of further communication devices (101a-c, 103a-c) using a second frequency band, the method comprising the steps of: receiving, by using the second frequency band, a control message from a further communication device (101a-c) of the plurality of communication devices (101a-c, 103a-c), the control message indicating that the further communication device (101a-c) is within the coverage area of the cellular communication network; and upon reception of the control message, starting to listen for messages from further communication devices of the plurality of communication devices (101a-c, 103a-c) using a first frequency band, wherein the method further comprises: as long as the communication device (103a-c) does not receive said control message, communicating with the further communication devices using a communication frame having a first control channel format, the first control channel format offering only communication resources for an ad-hoc communication mode; and upon reception of said control message, communicating with the further communication devices using a communication frame having a second control channel format, the second control channel format offering communication resources for an ad-hoc communication mode and a network assisted communication mode. receiving, by using the second frequency band, a control message from a further communication device (101a-c) of the plurality of communication devices (101a-c, 103a-c), the control message indicating that the further communication device (101a-c) is within the coverage area of the cellular communication network; and upon reception of the control message, starting to listen for messages from further communication devices of the plurality of communication devices (101a-c, 103a-c) using a first frequency band, wherein the method further comprises: as long as the communication device (103a-c) does not receive said control message, communicating with the further communication devices using a communication frame having a first control channel format, the first control channel format offering only communication resources for an ad-hoc communication mode; and upon reception of said control message, communicating with the further communication devices using a communication frame having a second control channel format, the second control channel format offering communication resources for an ad-hoc communication mode and a network assisted communication mode. as long as the communication device (103a-c) does not receive said control message, communicating with the further communication devices using a communication frame having a first control channel format, the first control channel format offering only communication resources for an ad-hoc communication mode; and upon reception of said control message, communicating with the further communication devices using a communication frame having a second control channel format, the second control channel format offering communication resources for an ad-hoc communication mode and a network assisted communication mode.