In a note dated 30 January 1959, the intelligence service of the French National Defence Department expresses its concern over the maintenance of French interests in Tunisia. Following the independence of Tunisia, the main institutions, such as internal and external security, the diplomatic apparatus and the administration, have gradually become more Tunisian. The monetary system became independent in 1958 with the establishment of the Tunisian Central Bank, the uncoupling of the dinar from the French franc and the withdrawal of the national currency from the franc area. Tunisia is also challenging the French military presence in Bizerte, a strategically important Mediterranean naval base.