The Greenland Treaty was an agreement between the member states of the European Communities concerning Greenland's exit from the European Communities. It followed the Greenlandic referendum in 1982 where voters supported their exit from the EC. The Treaty entered into force on 1 January 1985, and on 1 February 1985 Greenland formally withdrew from the European Communities. The Treaty arranged the exit of Greenland and amended earlier treaties of the European Communities. As such it is an integral part of the constitutional basis of the European Union. The decision to withdraw was made after Greenland had achieved self-rule and was made to ensure Greenland's rights to its fishing waters and to limit external influence.