Russian prosecutors admitted on Monday they had dropped charges against former Ukrainian Prime Minister Yulia Tymoshenko who had been accused of offering bribes to Russian officials as head of Ukraine's gas company.
A spokesman for Russia's military prosecutors said the statute of limitations had run out on the charges.
"In accordance with the requirements of Russian law, Yulia Tymoshenko agreed with the closure of the criminal case against her in connection with the ending of the statute of limitations," spokesman Mikhail Yanenko told.
Tymoshenko was a leading light in Ukraine's "Orange revolution" of street protests a year ago that infuriated Russia by overturning the Moscow-backed establishment.
Russian prosecutors suspended the arrest warrant when she was prime minister, reinstated it when she was sacked by former ally President Viktor Yushchenko in September, then suspended it again when she came to Moscow for questioning.
Now the charges have been dropped, Tymoshenko, whose party is seen as likely to come third in parliamentary elections in March, can travel to Russia without fear of arrest, Reuters reports.
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