Tymoshenko declared a hunger strike in April after claiming she was abused by prison authorities in Ukraine. She's serving a seven-year prison sentence after a conviction on charges she abused her authority in 2009 when, as prime minister, she helped broker a natural gas deal with Russian energy company Gazprom.
Russian Prime Minister Vladimir Putin said Tymoshenko could get medical treatment in Russia if permitted to do so by Ukrainian authorities.
Volodymyr Oliynyk, a lawmaker from Ukraine's Party of Regions, told the Interfax news agency there were no national or international means for Tymoshenko to get medical treatment in a foreign country.
"The statement (of Putin) is humanly understandable but mechanisms allowing convicted persons to receive medical treatment abroad are absent both in Russia and Ukraine today," he said.
Tymoshenko's family says her health is failing. Her supporters claim the charges were politically motivated.
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