Story highlights "This is not a restoration of the Cold War," White House spokesman says

Russian Foreign Ministry accuses opposition of "dictatorship and terror"

Opposition leader says missing President is trying to "avoid responsibility"

Ousted President Viktor Yanukovych hasn't been seen since Saturday

Ukraine's ousted President is a wanted man. He's also a missing man.

Viktor Yanukovych is not in Kiev. The mayor of Kharkiv, where Yanukovych was Saturday, says he hasn't seen him in a few days.

He's also apparently not hiding in a bunker in a Ukrainian Orthodox monastery, a church spokesman said, swatting down the latest speculation.

Ukraine's onetime -- and, by his account, current -- President is facing a warrant for the "mass killings" of civilians.

Over the weekend, he fled to Kharkiv, a pro-Russian stronghold near the border. And he tried to board a charter plane in the eastern city of Donetsk but was turned away because he didn't have documents.

In his last known public act, he delivered a televised speech Saturday from Kharkiv in which he rejected the parliament's ouster and vowed to fight.

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"I don't plan to leave the country. I don't plan to resign. I am the legitimate President," he said Saturday in the televised broadcast.

Critics weren't impressed.

"It's a remarkable situation when the most sought-after character in the country is the President of Ukraine, who is hiding and doing everything to leave the country, to avoid responsibility," opposition leader Vitali Klitschko said Monday.

Yanukovych's ouster and disappearance capped a weekend of dizzying developments after the parliament voted to oust Yanukovych as a concession to relentless protests, which led to the deadliest violence in the country since its independence 22 years ago.

Former Prime Minister Yulia Tymoshenko, 53, was freed from prison Saturday after 2½ years, most of them spent in a detention hospital.

Tymoshenko, a longtime opposition leader, has accepted an invitation for medical treatment in Germany, her press officer Marina Soroka said. She will be attending a European People's Party summit there.

On Monday, the Ukrainian Parliament continued work toward its goal of having a full interim government in place by Tuesday, naming a new chief prosecutor, security service chief and central bank head.

Parliament had already named Speaker Oleksandr Turchinov to serve as acting President. He is a longtime ally of Tymoshenko's.

The head of Ukraine's electoral commission, Konstantin Khivrenko, said the campaign to elect a new president will begin Tuesday, three months before the May 25 election date set by authorities.

Russia's Foreign Ministry criticized those elections Monday, saying Ukraine's parliament was acting rashly, and accused lawmakers of discriminating against ethnic Russians by excluding them from the reform process.

"A course has been set for suppressing those who disagree in different regions of Ukraine with methods of dictatorship and terror," the Foreign Ministry said.

Some protesters gathered Monday outside the Ukrainian parliament shouting "shame" in response to what they see as a lack of transparency on the part of lawmakers.

Yanukovych's decision to scrap a European Union trade deal in favor of one with Russia prompted the protests in November.

Now, the country's new leaders have made clear that Kiev's return to European integration will be a priority. But in doing so, they risk losing the largess that the Kremlin had bestowed on Yanukovych.

Taking no chances, interim Finance Minister Yury Kolobov proposed Monday that an international donor conference be held in the next two weeks. Ukraine, he said, will need $35 billion in foreign assistance by the end of 2015.

Yanukovych has traditionally looked upon eastern Ukraine, near Russia, as his traditional support base. Russian culture and language are predominant there.

People in the east are suspicious of the Europe-leaning views of those in western Ukraine, who were at the heart of the protests against Yanukovych that filled central Kiev for months.

The big question: How will Russian President Vladimir Putin respond? He's been Yanukovych's chief ally, and Ukraine is in his backyard. Will he act militarily?

The U.S. has expressed support for the action of parliament. U.S. Secretary of State John Kerry spoke with the Russian foreign minister Sunday and asked Russia not to use military force in the country, according to a senior State Department official.

The State Department also warned U.S. citizens to defer all nonessential travel to Ukraine.

"We have been very clear that we support an independent and unified Ukraine and that the idea of separation or partition or division is not in the interest of the Ukrainian people, of the Ukrainian nation, of Europe, or Russia, or the United States," White House spokesman Jay Carney told reporters Monday.

"This is not a competition between East and West. This is not a restoration of the Cold War. This is about the Ukrainian people and their future," he said.