WATCH: Supporters of former Prime Minister Yulia Tymoshenko protest outside the courtroom and pelt former President Viktor Yushchenko's car with eggs.
Cries of "shame!" greeted Ukraine's former president, Viktor Yushchenko, as he entered a Kyiv court to testify against his former prime minister, Yulia Tymoshenko, in her abuse-of-power trial.
Tymoshenko, currently the country's leading opposition figure, is charged over a 2009 deal she signed with Russian Prime Minister Vladimir Putin that raised the price Ukraine paid for its gas.
The 50-year-old Tymoshenko faces up to 10 years in jail if convicted on charges she says are politically motivated.
In court on August 17, Yushchenko said the terms of the 2009 deal had looked bad but that he did not have the authority to prevent Tymoshenko from signing it.
He said Russia had initially offered a more reasonable price, but Tymoshenko turned the offer down -- and was later forced to accept a much higher price.
"Putin said, word for word, 'I personally offered [Tymoshenko] the price of $250 per 1,000 cubic meters and reexports,'" Yushchenko told the court in describing the 2008 talks leading up to the deal. "But [Putin said] she replied, 'No.' And that's what derailed the negotiations."
"There was a complete breakdown in the negotiations," he added.
Yulia Tymoshenko in the Kyiv courtroom on August 15
Yushchenko's court appearance comes out of a long history with Tymoshenko. The two used to be a team, working at the forefront of the country's 2004 Orange Revolution, a series of protests over the disputed election of rival Viktor Yanukovych that ultimately handed Yushchenko the presidency.
Tymoshenko served as prime minister twice under Yushchenko's 2005-2010 administration.
But the two quickly fell out, which some say helped pave the way for the return of Yanukovych as the current president. Yushchenko and Tymoshenko both ran against him in the country's tightly contested 2010 presidential election.
The case against Tymoshenko is divisive in Ukraine. Lyudmila, a protester taking part in an anti-Tymoshenko protest outside the Kyiv court today, told RFE/RL's Ukrainian Service, "Yulia Tymoshenko must answer for her actions and crimes against the Ukrainian people and state."
WATCH: Protests continued outside the Kyiv court hearing Tymoshenko's case. Her opponents want her brought to justice, while her supporters believe she is all that stands against authoritarianism in Ukraine (in Ukrainian).
Meanwhile, supporters of the Orange Revolution heroine charge the president, known for his close ties to Russia, of using the legal proceedings -- not to mention a possible jail sentence -- as a way to limit Tymoshenko's political activities.
"I come to the court every day. I come here for myself," Svitlana, a Tymoshenko supporter, told RFE/RL's Ukrainian Service outside the court. "If Tymoshenko is imprisoned, we're all imprisoned. They will knock on my door and say, 'Hey, you’re wearing vyshyvanka [traditional clothing], so go to the prison.' I come here for freedom, for my own freedom."
Both the United States and the European Union have condemned Tymoshenko's trial, saying it appears to be the politically motivated prosecution of an opposition figure.
The trial is expected to draw added international attention when Ukraine celebrates 20 years of independence next week.
written by Kristin Deasy, with contributions from Yeugen Solonyna and Olena Removska of RFE/RL's Ukrainian Service and agency reports