Refer to the input text as context and select the correct relationship between 'Naftogaz' and 'Ukraine' from the available options.
Options: position held, owned by, parent organization, distribution format

"Since the additional agreement between Naftogaz and Gazprom is expiring on June 30, and the terms of further Russian gas deliveries to Ukraine were not agreed at today's trilateral talks in Vienna, Naftogaz is suspending purchases from the Russian company," the Ukrainian firm said in a statement.
owned by