The present invention concerns a method for determining if a collaboration session may be established between a first wireless telecommunication device and a second wireless telecommunication device of a wireless cellular telecommunication network. The second wireless telecommunication device: receives through the telecommunication network, a message comprising at least one information representative of a time to transfer or receive a predetermined radio signal by the second wireless telecommunication device, determines at least from time of reception of the message and from the time to transfer or receive the predetermined radio signal if a collaboration session between the first and the second wireless telecommunication may be established.