WASHINGTON (AP) — The Trump administration notified international partners on Thursday that it is pulling out of a treaty that permits 30-plus nations to conduct unarmed, observation flights over each other's territory — overflights set up decades ago to promote trust and avert conflict.

The administration says it wants out of the Open Skies Treaty because Russia is violating the pact, and imagery collected during the flights can be obtained quickly at less cost from U.S. or commercial satellites. Exiting the treaty, however, is expected to strain relations with Moscow and upset European allies and some members of Congress.

President Dwight Eisenhower first proposed that the United States and the former Soviet Union allow aerial reconnaissance flights over each other's territory in July 1955. At first, Moscow rejected the idea, but President George H.W. Bush revived it in May 1989, and the treaty entered into force in January 2002. Currently, 34 nations have signed it; Kyrgyzstan has signed but not ratified it yet.