In what is known as a state of defence (when the country is under attack by armed force or imminently threatened with such an attack), the Joint Committee exercises the rights of the Bundestag and the Bundesrat if there are insuperable obstacles to timely convening of the Bundestag or if the Bundestag cannot muster a quorum.
The Länder, or federal states, work together within their own sphere of responsibility in the Conference of Minister-Presidents and the various sector-specific Conferences of Ministers. That means these bodies are neither federal organs nor part of the Bundesrat as such.