The process of secession was regulated by the Constitutional Charter of Serbia and Montenegro adopted on 4 February 2003 by both Councils of the Federal Assembly of the Federal Republic of Yugoslavia, in accordance to the 2002 Belgrade Agreement between the governments of the two constitutive republics of the state then known as the Federal Republic of Yugoslavia, Montenegro and Serbia. Article 60 of the constitution required that a minimum of three years pass after its ratification before one of the member states could declare independence. The same article specified the referendum as necessary for this move.