Ukraine's divisive opposition icon Yulia Tymoshenko completed an improbable return to politics Thursday by announcing plans to contest snap polls to replace the ousted pro-Russian president whose regime sent her to jail. "I intend to run for president of Ukraine," the 53-year-old told reporters after gingerly walking into a press room with the help of a walking stick she uses due to chronic back pain. The brief but dramatic announcement encapsulates the spectacular changes that have swept the economically struggling and culturally splintered ex-Soviet state of 46 million in the past few weeks. The country is due to hold a presidential election on May 25 after the ouster of pro-Kremlin leader Viktor Yanukovych last month, the culmination of three months of pro-EU protests. Tymoshenko -- one of the most charismatic and outspoken leaders of Ukraine's 2004 pro-democracy Orange Revolution -- lost a close presidential poll to Yanukovych in 2010 after heading two pro-Western cabinets that became embroiled in internal squabbles and eventually lost popular support. Her political downfall after the 2010 vote was rapid and seemingly fatal. Yanukovych's government quickly launched a series of criminal probes against his rival that led to a controversial trial over Tymoshenko's role in agreeing a 2009 gas contract with Russia that many Ukrainians thought came at too high a price. Tymoshenko was convicted in October 2011 for abuse of power and sentenced to a seven-year jail term that Western nations denounced as a brazen show of selective justice. But she emerged triumphantly from the state hospital in which she had spent most of her sentence under guard on February 22 -- the day parliament ousted Yanukovych for his role in the deaths of nearly 100 protesters that month. Tymoshenko immediately went to the protest square in the heart of Kiev that also played the central role in the 2004 pro-democracy revolt. But the crowd's reception was guarded on this occasion -- a sign of the wariness among many of the ugly corruption allegations that have stained Tymoshenko's reputation in recent years. - 'I stand out' - Some analysts believe the pro-Western movement that Tymoshenko once headed is now looking to a new generation of leaders who played a more prominent role in the latest protests and who  hold key positions in the new interim government. "Her support has slipped significantly since 2010," said Valeriy Chaly of the Razumov political research centre. "People like (Prime Minister Arseniy) Yatsenyuk have proven themselves to be very capable." Tymoshenko on Thursday attempted to paint herself as a compromise figure who could look after the interests of her old supporters while reassuring Russian speakers who have traditionally relied on the Kremlin for support. "I will be able to find a common language with everyone who lives in the east," Tymoshenko said before adding that she still viewed Russian President Vladimir Putin as "Ukraine's enemy number one". Critics have long accused Tymoshenko of being a political chameleon who lacked ideals and frequently changed positions in her thirst for power. Putin has famously said he viewed Tymoshenko as a trusted partner with whom he could do business despite her seeming allegiance to closer ties with the West. Tymoshenko on Thursday vowed to commit herself to breaking the close links between big business and government that have allowed a select group of tycoons and political insiders to enrich themselves through shadowy deals. "I stand out from all the other presidential candidates because I will actually be able to do this: I will be able to break up these huge clan-like corporations," she said. Tymoshenko has considerable ground to make up if she hopes to win the election. An opinion poll published Wednesday by four respected Ukrainian research firms put her in third place with just over eight percent of the prospective vote. Chocolate baron Petro Poroshenko ranked first with the backing of almost a quarter of respondents. Former boxing champion turned opposition leader Vitali Klitschko was second with almost nine percent. But some analysts said Tymoshenko still had the political wherewithal to mount a powerful challenge that should at least secure her a place in a second-round runoff. "Tymoshenko knows how to wage a political campaign," said Kiev's Global Strategies Institute director Vadym Karasyov. "It is much too premature to speak of a clear winner in this election."