France also adheres to international agreements which provide for application modalities for the right of asylum, such as the 1951 United Nations (UN) Convention Relating to the Status of Refugees (ratified in 1952), the additional 1967 protocol; articles K1 and K2 of the 1992 Maastricht Treaty as well as the 1985 Schengen Agreement, which defined EU immigration policy. Finally, the right of asylum is defined by article 18 of the Charter of Fundamental Rights of the European Union.