at least 30 days, which could be extended to 120 days, if resupplied. The Battlegroups are designed to deal with those tasks faced by the Common Security and Defence Policy, namely the Petersberg tasks (military tasks of a humanitarian, peacekeeping and peacemaking nature). Planners claim the Battlegroups have enough range to deal with all those tasks, although such tasks ought to be limited in "size and intensity" due to the small nature of the groups. Such missions may include conflict prevention, evacuation, aid deliverance or initial stabilisation. In general these would fall into three categories; brief support of existing troops, rapid deployment preparing the ground for larger forces or small-scale rapid response missions. Structure A Battlegroup is considered to be the smallest self-sufficient military unit that can be deployed and sustained in a theatre of operation. EU Battlegroups are composed of approximately 1,500 troops; plus command and support services. Since March 2022, the EU has been planning to increase their size to up to 5,000 troops per battlegroup by 2025. There is no fixed structure, a 'standard' group would include a headquarters company, three infantry companies and corresponding support personnel. Specific units might include mechanised infantry, support groups (e.g. fire or medical support), the combination of which allows independent action by the group on a variety of tasks. The main forces, extra support and "force headquarters" (front line command) are contained within the Battlegroup "package", in addition there is the operation headquarters, located in Europe. Battlegroups The initial thirteen Battlegroups were proposed on 22 November 2004. Further battlegroups have joined them since then. Contributions Larger member states will generally contribute their own Battlegroups, while smaller members are expected to create common groups. Each group will have a 'lead nation' or 'framework nation' which will take operational command, based on the model set up during the EU's peacekeeping mission in the Democratic Republic of the Congo (Operation Artemis). Each group will also be associated with a headquarters. Three non-EU NATO countries, Norway, Turkey, and North Macedonia, participate in a group each, as well as one non-EU non-NATO country, Ukraine. From 1992 to 2022, Denmark had an opt-out clause in the Treaty of Maastricht and was not obliged to participate in the Common Security and Defence Policy, but following a 1 June 2022 referendum in favour of abolishing the opt-out, Denmark joined the CSDP a month later on 1 July 2022. Malta