An international team of doctors has begun the medical examination of jailed former Ukrainian Prime Minister Yulia Tymoshenko.
Tymoshenko has complained of deteriorating heath since being jailed in October for seven years for abuse of office.
Tymoshenko claims her health problems stem from mistreatment at the prison, something Kyiv denies.
Earlier, the international team of doctors -- including three doctors from Canada and two from Germany -- arrived at the Kachanivska prison in Kharkiv, some 500 kilometers from the capital, Kyiv.
Ukrainian Deputy Health Minister Raisa Moiseyenko told reporters outside the prison the examination could take some time.
"As of today, all these questions have been resolved, and an examination of Yulia Volodymyrivna [Tymoshenko] is now in progress," Moiseyenko said. "Medical examination is a time consuming process, partly because there are English speaking specialists there and some translation has to be done. There are translators present there, ones Yulia Volodymyrivna trusts. We have agreed on it. So, the duration of examination can be rather long."
Reports out of Ukraine say Tymoshenko first refused to see the international team.
Her defense counsel, Serjiy Vlasenko, said that was because of the presence of Ukrainian doctors who Tymoshenko fear will be under political pressure to issue her a clean bill of health.
But later on February 14 the team was finally admitted to see her.
Outside the prison, some 100 supporters carried placards of Tymoshenko, demanding her release.
Supporters and much of the international community suspect the case against Tymoshenko is politically motivated with the aim of silencing a leading figure of Ukraine's opposition.
In December, the European Union delayed the signing of a major trade agreement with Ukraine due to concerns over the jailing of Tymoshenko.
President Viktor Yanukovych has ignored calls to release Tymoshenko, who is now facing fresh charges dating back to the 1990s when the so-called gas princess ran a private natural gas trading company, United Energy Systems of Ukraine.
Tymoshenko lost to Yanukovych in a tight presidential race in 2010.
Compiled from agency reports