KIEV, Ukraine — Prime Minister Yulia Tymoshenko's pro-Western Orange coalition dissolved Tuesday as her former allies turned against her, setting her up to be ousted in a no-confidence vote.
The development spells the final repudiation of the Orange Revolution Tymoshenko helped lead in 2004, and paves the way for Ukraine's new Kremlin-friendly president to consolidate his power.
President Viktor Yanukovych defeated Tymoshenko in last month's election, but she has been a thorn in his side, refusing to resign and challenging the vote results.
In a sign that she will be removed, speaker Volodymyr Lytvyn told parliament Tuesday the Orange coalition had been unable to prove it still had majority support in the 450-seat chamber.
"This coalition did not come up with enough votes ... I therefore announce the termination of this coalition's activity," Lytvyn said.
Russia's new ambassador arrived in Kiev to congratulate Yanukovych on now appears to be total victory.
Ukraine's political parties must now form a new majority coalition, and are most likely to group around Yanukovych's Party of Regions. Yanukovych says that if no majority can be reached he will disband parliament and call elections.
Tymoshenko lashed out at Lytvyn, who is also a leader of the Orange forces in parliament, for "illegally ruining the democratic coalition" and paving the way for Yanukovych's "anti-Ukrainian dictatorship."
"This was the last barricade worth defending if we wanted to protect our independence, sovereignty, strength and the European development of our country," Tymoshenko said in a televised speech.
"History will hold him responsible," she said.
Tymoshenko laid out no plan of action. She said only that she would seek to unite Ukraine's "truly democratic and patriotic forces."
Parliament is set to hold a confidence vote Wednesday on Tymoshenko's government.
"As of today, we have a majority capable of creating a coalition in parliament, and we definitely have a majority capable of holding a no-confidence vote against the government," said Oleksandr Yefremov, a lawmaker with Yanukovych's party.
"The dissolution of the coalition makes Tymoshenko's ouster inevitable," said Viktor Nebozhenko, a political analyst in Kiev. "The Orange forces have been defeated on every front."
The Orange coalition, formed in December 2008, was loosely centered on the political ideals of the Orange Revolution, a series of massive street protests in 2004 led by former President Viktor Yushchenko and Tymoshenko.
Those protests against vote fraud resulted in the Supreme Court overturning Yanukovych's election victory in 2004. Yushchenko, a reformer who wanted closer integration with the West, won a revote. Tymoshenko became his prime minister.
But their constant bickering and inability to deliver on promises of European integration and economic growth fueled Yanukovych's comeback. He defeated Tymoshenko in a Feb. 7 runoff by 3.5 percentage points.
Yushchenko, whose mysterious poisoning in 2004 made him a martyr for the Orange cause, appears now to have tacked with Ukraine's shifting political winds. Members of his party, Our Ukraine, are expected to join the coalition forming around Yanukovych.
"The new coalition will combine the Party of Regions, Our Ukraine, and Lytvyn's bloc," said Yury Yakimenko, a political analyst at the Razumkov Center, a Kiev think tank.
This would not be the first time Tymoshenko, known for her sharp wit and political cunning, is removed as prime minister.
In 2005, soon after the Orange Revolution brought them to power, Yushchenko dismissed Tymoshenko for mismanagement. She regained the post two years later.
This time, the failure of her coalition will likely force her back into an opposition role, but she will retain significant clout as the leader of the second-biggest faction in parliament.
Russian Ambassador Mikhail Zurabov presented his credentials Wednesday to Yanukovych, renewing diplomatic relations between the two countries for the first time since August 2009, when the Kremlin declined to send an ambassador to Kiev until Yushchenko left office.
Yushchenko's efforts to take Ukraine out of Russia's orbit and join NATO and the European Union infuriated the Kremlin.
Yanukovych, whose base of support is in Ukraine's Russian-speaking east, has said he would not seek membership in either organization. He is expected to invigorate ties with Russia through energy interdependence and military cooperation, and plans to visit Moscow on Friday.
"Allow me to express my respect for the Ukrainian people and wish you success in your role as president," Zurabov told Yanukovych during a televised ceremony.
Shuster reported from Moscow. Associated Press Writer Yuras Karmanau in Minsk, Belarus, contributed to this report.