"Payments have started [and] $7.5 million have already been paid to Russia," Pshonka said referring to the debt owed by the state-run energy company once headed by former Ukrainian Prime Minister Yulia Tymoshenko.
Tymoshenko has been jailed over abuse of office charges that stemmed from her part in negotiating a gas deal with Russia in 2009.
Tymoshenko and her attorneys have said the charges against her were trumped up by President Viktor Yanukovych.
Tymoshenko, who is serving a seven-year sentence, also has been accused of tax evasion and forgery, charges her defense team also consider to be retribution by a political rival.
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