NASA said Wednesday that it was suspending most contacts with Russian space-agency officials, illustrating how rapidly the U.S.-Russian relationship is deteriorating in the wake of Russia’s annexation of Crimea.

The one exception, NASA said, would involve operations of the international space station, the primary space collaboration between the two countries.

Otherwise, the extent of NASA’s break in relations is broad and includes “travel to Russia and visits by Russian government representatives to NASA facilities … and teleconferences or videoconferences,” according to an email to NASA officials.

As the confrontation over Ukraine intensified, it became untenable for the Obama administration to continue sending NASA officials to Russia or hosting their space-agency officials in the U.S. as the U.S. cut off trade talks and military cooperation and threw Russia out of the Group of 8.

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Defense Secretary Chuck Hagel has also directed the Air Force to review the use of Russian engines in rockets that send U.S. military satellites into orbit.