Amendment to the Iran Nonproliferation Act of 2000 - Amends the Iran Nonproliferation Act of 2000 to authorize the National Aeronautics and Space Administration (NASA) to make extraordinary payments that may otherwise be prohibited under such Act to the Russian Aviation and Space Agency if the President has notified the Congress in writing that such payments are necessary to: (1) ensure the safety of the crew aboard the International Space Station; and (2) maintain continued operation of the International Space Station during such period that the U.S. Space Shuttle fleet is grounded due to an accident or other safety-related matter.