Share files with colleagues outside of the team/group

Hello. I have a group in Teams dedicated to a department and various channels for the topics we discuss. In one of the channels we prepare information required by the communications department. They are not part of the process and just receive input, so they are not members of the group. Is it possible to give them access only to one channel or to the files they require? Or is it necessary that they subscribe to the channel? Thanks a lot for the help!