https://197lines.com/the-us-and-mongolia-sign-an-open-skies-civil-aviation-agreement-mongolias-national-airline-miat-mongolian-airlines-flies-to-europe-and-asia-but-not-to-the-us
The US and Mongolia to sign an 'Open Skies' civil aviation agreement; Mongolia's national airline, MIAT Mongolian Airlines, currently flies to Europe and Asia, but not to the US