Ukraine Appoints New Ambassador to US Zelenskyy appointed Olha Stefanishyna as Ukraine's ambassador to the United States Stefanishyna replaces Oksana Markarova, who served six years as ambassador Zelenskyy emphasized US agreements for defense and Ukraine's security. Politics | Defense | Foreign Affairs United States | Ukraine Volodymyr Zelenskyy | Olha Stefanishyna | Oksana Markarova 2 weeks ago