Ukrainian President Volodymyr Zelensky dismisses Ambassador to the US Olga Stefanishyna amid ongoing diplomatic efforts for air defence support. Kyiv (Ukraine): Ukrainian President Volodymyr Zelensky signed an official decree on Monday relieving Olga Stefanishyna of her duties as Ambassador to the United States. The decision follows a broader Cabinet reshuffle initiated last month, though her departure was largely anticipated in diplomatic circles. The official announcement comes at a delicate diplomatic juncture for Kyiv. The presidential decree did not immediately name a replacement for the key diplomatic post in Washington.