Rio Treaty

Rio Treaty (Inter-American Treaty of Reciprocal Assistance), signed Sept. 2, 1947, and originally ratified by all 21 American republics. Under the treaty, an armed attack or threat of aggression against a signatory nation, whether by a member nation or by some other power, will be considered an attack against all (see Pan-Americanism). The treaty provides that no member can use force without the unanimous consent of the other signatories, but that other measures against aggressors may be approved by a two-thirds majority. It differs from previous inter-American treaties in that it is a regional treaty within a larger international organization; it recognizes the higher authority of the Security Council of the United Nations.

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Rio Treaty

 officially Convention on Biological Diversity

International environmental agreement approved at the 1992 Earth Summit in Rio de Janeiro. Negotiations began in 1988 under the auspices of the United Nations Environment Program. Its goals are the conservation of the planet's biodiversity and the fair use of its resources. By the early 21st century, more than 185 governments were party to the agreement.