Treaty on Open Skies

The Treaty on Open Skies establishes a program of unarmed aerial surveillance flights over the entire territory of its participants. The treaty is designed to enhance mutual understanding and confidence by giving all participants, regardless of size, a direct role in gathering information about military forces and activities of concern to them. It entered into force on 1 January 2002, and currently has 34 party states. The idea of allowing countries to openly surveil each other is thought to prevent misunderstandings (e.g., to assure a potential opponent that one's country is not about to go to war) and limit the escalation of tensions. It also provides mutual accountability for countries to follow through on treaty promises.

The concept of "mutual aerial observation" was initially proposed to Soviet Premier Nikolai Bulganin at the Geneva Conference of 1955 by U.S. President Dwight D. Eisenhower; however, the Soviets promptly rejected the concept and it lay dormant for several years. The treaty was eventually signed as an initiative of U.S. president (and former Central Intelligence Agency Director) George H. W. Bush in 1989. Negotiated by the then-members of NATO and the Warsaw Pact, the agreement was signed in Helsinki, Finland, on 24 March 1992.^[2]

On 22 November 2020, the United States withdrew from the treaty,^[3] and on 15 January 2021, Russia also announced its intention to leave, citing the U.S. withdrawal and the inability of member nations to guarantee that information gathered would not be shared with the U.S.^[4] Russia formally withdrew in December 2021.^[5]