Tymoshenko was accused of bribing Russian defense officials while she headed Ukraine's main gas distributor in the mid-1990s. She denied the Russian charges, saying they were politically motivated.
Tymoshenko, one icon of the Orange Revolution, was dismissed as prime minister in early September.
Tymoshenko met with Russian prosecutors in Moscow the same month and the international arrest warrant against her was dropped.
Tymoshenko's bloc is a top contender in the March parliamentary elections.