KIEV, Ukraine -- Ukraine's ex-prime minister Yulia Tymoshenko was Wednesday placed under investigation for abuse of power and ordered not to leave Kiev, in the gravest legal action yet against the Orange Revolution leader.
"She is under a pledge not to leave town," the spokesman for Ukraine's general prosecutors Yury Boichenko told AFP, saying Tymoshenko was being investigated for abuse of power and duties.
The order represented the most serious legal trouble for Tymoshenko since she was forced out of her post after the victory of the Kremlin-friendly Viktor Yanukovych in presidential elections earlier this year.
Tymoshenko, known for her long braid of golden hair and tight-fitting designer dresses, said earlier that the authorities had opened a criminal probe against her for misspending state money Ukraine received from selling greenhouse emission quotas under the Kyoto Protocol.
"I have just learnt from an investigator that a criminal probe has been started against me personally because ostensibly environmental money during the crisis was spent on pensions," she said.
She added sarcastically the probe had been opened "because I committed a grave crime -- because I paid people pensions when the country was truly in crisis".
She also told reporters she had been questioned by investigators earlier Wednesday but formal charges had not yet been brought against her because she was without her lawyer.
Tymoshenko said she told the investigators that the money in question -- 320 million euros (425 million dollars) -- was not misappropriated and is intact.
Analysts said Yanukovych's government was preparing to tackle new unpopular reforms and wanted to make sure the former premier did not take people into streets to rally against the authorities.
"Taking into consideration that preparations for new unpopular measures are starting they would like to neutralize Tymoshenko ahead of time so that she is more involved with investigators rather than political mobilisation campaigns," said Volodymyr Fesenko, head of the Kiev-based Gorshenin Management Institute.
He said that the authorities would want to avoid arresting her as it would play into Tymoshenko's hands and turn her into a political martyr, exactly the goal she is seeking to achieve.
The charge carries a sentence of between seven and 10 years.
Hryhoriy Nemyria, deputy head of Tymoshenko's Batkivshchyna party, said in a statement she had planned to go to Brussels where she was to meet European leaders and Yanukovych was "afraid to let Yulia Tymoshenko go abroad".
Tymoshenko -- one of the champions of the Orange Revolution that brought pro-Western leaders to power in 2005 -- is expected to return for more questioning on Monday.
"I will certainly be with my lawyer," she said in comments posted on her official website, adding that the probe into pensions meant that "these authorities want to go far."
In February, Tymoshenko lost a hard-fought presidential election battle to Yanukovych, leading her to step down as prime minister in early March and go into opposition.
Since then she has accused Yanukovych of repeated attempts to silence her and sharply criticised his policies, particularly his efforts to build closer relations with Soviet-era master Russia.
A charismatic politician, Tymoshenko is a veteran of Ukraine's hardball political scene who has experienced run-ins with the law before.
In 2001, she was detained for several weeks on charges of forgery and natural gas smuggling that were later dropped.