NASA has suspended contact with Russian government representatives, citing ongoing violations of Ukraine's sovereignty and territorial integrity, FoxNews.com confirmed.
"Given Russia's ongoing violation of Ukraine's sovereignty and territorial integrity, NASA is suspending the majority of its ongoing engagements with the Russian Federation," NASA spokesman Allard Beutel told FoxNews.com.
News of NASA's decision came Wednesday afternoon when an internal letter written by a top official was leaked.
'The choice here is between fully funding the plan to bring space launches back to America or continuing to send millions of dollars to the Russians. It’s that simple.'
“This suspension includes NASA travel to Russia and visits by Russian Government representatives to NASA facilities, bilateral meetings, email, and teleconferences or videoconferences,” states the letter, which was written by Michael F. O'Brien, NASA’s associate administrator for international and interagency relations.
However, ongoing activities at the International Space Station (ISS) have been exempted from the rules, as well as “multilateral meetings held outside of Russia that may include Russian participation.”
"NASA and Roscosmos will, however, continue to work together to maintain safe and continuous operation of the International Space Station," Beutel confirmed.
There are currently two Americans onboard the ISS.
Amid the crisis in Crimea, there is growing concern over the U.S.'s reliance on Russia for human transport to and from the International Space Station since retiring the American space shuttle program.
The U.S. relies on the Russian Souyez rockets for all manned trips to and from space. NASA signed an agreement with Russia last April, governing six flights through 2017, at a cost of $70.7 million per seat.
"NASA is laser focused on a plan to return human spaceflight launches to American soil, and end our reliance on Russia to get into space," said Beutel. "This has been a top priority of the Obama Administration’s for the past five years, and had our plan been fully funded, we would have returned American human spaceflight launches – and the jobs they support – back to the United States next year."
Beutel said NASA is looking at a 2017 launch from U.S. soil. "The choice here is between fully funding the plan to bring space launches back to America or continuing to send millions of dollars to the Russians. It’s that simple."
In early March, NASA Administrator Charles Bolden insisted that the U.S. and Russia’s space partnership was not being strained over tensions in Ukraine.
"Right now, everything is normal in our relationship with the Russians," Bolden said at the time. "I think people lose track of the fact that we have occupied the International Space Station now for 13 consecutive years uninterrupted, and that has been through multiple international crises."