NASA has been added to the list of U.S government agencies prohibited from contacting Russian government representatives, though operation of the International Space Station is exempt from the ban, officials said on Wednesday.
"This suspension includes NASA travel to Russia and visits by Russian government representatives to NASA facilities, bilateral meetings, email, and teleconferences or video conferences. At the present time, only operational International Space Station activities have been excepted," NASA Associate Administrator Michael O'Brien wrote in a memo to employees that was posted on the NASAWatch.com website.
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The gesture may be largely symbolic. The only major space project under direct U.S.-Russia control is the space station, a $100 billion research laboratory, owned by 15 nations, which flies about 250 miles (about 400 km) above Earth.
Three Russian cosmonauts, two U.S. astronauts and one Japanese astronaut currently are living aboard the orbital outpost.
"It's not a major deal - and that's appropriate because space cooperation is one of the few things that actually has gone relatively well with the Russians," said Scott Pace, director of George Washington University's Space Policy Institute.
"If we want to express our opposition to their actions I hope that we would choose other instruments," he added.
The sanctions stem from Russia's annexation of Ukraine's Crimea peninsula.