The current legal framework of the Common Security and Defence Policy (CSDP) was set in stone in 2009 by the Treaty on European Union (TEU). The CSDP is described in detail by the Articles 41 to 46 of the TEU. Article 41, paragraph 2 of the TEU, prohibits expenditure arising from military operations from being charged to the EU budget. Therefore, a large percentage of the military operations costs should be covered by the EU Member States (MS). According to Article 42 of the TEU, the Council of the European Union (EU) and the European Council unanimously decide on matters related to the CSDP.