 In this capacity it has worked closely with Washington to advance non-proliferation further.In 2006 it joined with its Central Asian neighbors Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan to affirm that the entire region would forever be a nuclear weapons free zone.To be sure, the U.S. initially opposed this out of fear that it would exclude the transport of nuclear material across the region, but in the end this step, too, earned strong endorsements from Washington.