MOSCOW - Russian President Vladimir Putin offered a vigorous defense of his country's intervention in Ukraine, saying Tuesday that the pro-Russian former government in Kiev was illegally overthrown and that the man he regards as Ukraine's legitimate president asked him for military help.
But he asserted that the troops wearing unmarked uniforms in Ukraine's Crimea region are members of local self-defense groups - not Russian forces, as observers on the scene have said.
In his first public comments about the crisis since President Viktor Yanukovych was deposed Feb. 22, Putin described Ukraine as lawless and suggested that Ukrainians appeared unable to run their own country. He said masked militants were "roaming the streets of Kiev" - even though the Ukrainian capital has remained calm in recent days.
"This is a humanitarian mission," he said.
After days of heightening tension, Putin's remarks appeared to suggest that Russia could refrain from escalation - if Ukraine gets its house in order. Hours later, Russia proclaimed the successful test launch of an intercontinental ballistic missile in Asia, a move unrelated to the crisis but a demonstration to Ukraine and the West of Russia's military prowess.
President Barack Obama and Secretary of State John Kerry rejected Putin's assertions about the situation in Ukraine, with Kerry charging during a visit to Kiev that "Russia has been working hard to create a pretext for being able to invade further.
They said it was not true that Russia needs to send in troops to safeguard Russians or Russian speakers in Ukraine from violent reprisals.
Dismissing Moscow's purported concerns, Obama said Russia was "seeking through force to exert influence on a neighboring country."
Putin, however, accused the United States of engineering Ukraine's troubles, suggesting that it was using Ukrainians as guinea pigs in some kind of misguided experiment.
"They sit there across the pond as if in a lab running all kinds of experiments on the rats," he told a small group of reporters in a nationally televised meeting at his country house outside Moscow. "Why would they do it? No one can explain it."
Despite Ukrainian and Western reports, Putin said that Russia has not sent additional troops to Crimea to augment those already based there and that Russian troops had only been put on alert to defend their bases.
In Kiev, his remarks were greeted with less ferocity than might have been expected. The new government is under enormous pressure from the Russian intervention and from unrest in eastern cities, coupled with a financial crisis. It is treading carefully. As Crimea slipped further into Russian control Tuesday, Ukrainian military units there stood their ground but were careful not to provoke a conflict.
In Ukraine's parliament, there was talk of finding a way to give Crimea more autonomy if it agrees to remain a part of Ukraine. The region has scheduled a March 30 referendum on independence or accession to Russia, though Crimea's new leader, Sergei Aksyonov, said Tuesday that he wants to hold the vote sooner. Kerry, echoing the views of many in Kiev, said Russia had installed Aksyonov in a hurried and rigged selection process last week.
Oleh Tiahnybok, the head of the nationalist All-Ukrainian Union "Svoboda" party, said, "The Kremlin is attempting to use blackmail to solve its strategic plans. Ukraine should not succumb to it."
And Russia's intervention, he declared, is a failure: "Ukrainians are not running with outstretched arms toward the occupiers."
It has been, all around, an unusual confrontation. After a week of deadly fighting in the streets of Kiev led to Yanukovych's overthrow, the Russian takeover of Crimea has been swift yet bloodless. The atmosphere in Kiev is hardly that of a capital dealing with an intervention by a powerful neighbor.
Aksyonov said Tuesday that most of the Ukrainian military forces in Crimea have sworn allegiance to his new regional government. Officials in Kiev said that is not true.
Young men in Ukrainian self-defense groups said Tuesday that they are ready to take on the Russians but do not need to join the national army to do so.
In a stately hall that normally houses an association for architects, a militia had stashed construction hard hats and bicycle helmets atop a stairway, ready to be grabbed if things turn violent. The marble floors were lined with mattresses and sleeping bags.
"I'm ready to fight the Russians," said Vitaliy Vovk, 24, an event planner and the militia commander. "But I'm hoping there will be no war, that it's just Putin flexing his muscles."
Putin said the whole operation is a friendly one, designed to help out a fraternal nation. But he described Ukraine as deeply troubled, telling his interviewers that corruption and social stratification there are even worse than in Russia.
"Out there, they are beyond anything we can imagine," he said. "This revolutionary situation has been brewing for a long time."
So it's understandable why the protesters on the Maidan, Kiev's Independence Square, wanted an uprising, he said. But they went about it the wrong way, he said, describing the situation as Ukraine swapping one "set of thieves" - Yanukovych's - for another, a reference to the present government.
Putin said that if he decides to send in the Russian military, he would have legal grounds to do so. Russia has displayed a letter from the ousted president asking for military help in suppressing the revolt. The current government is illegitimate, Russia contends, because Yanukovych was not properly removed from power in a formal impeachment.
"What is our biggest concern?" Putin asked. "We see the rampage of reactionary forces, nationalist and anti-Semitic forces going on in certain parts of Ukraine, including Kiev."
"We understand what worries the citizens of Ukraine, both Russian and Ukrainian, and the Russian-speaking population in the eastern and southern regions of Ukraine," he said. "It is this uncontrolled crime that worries them. Therefore, if we see such uncontrolled crime spreading to the eastern regions of the country, and if the people ask us for help, while we already have the official request from the legitimate president, we retain the right to use all available means to protect those people. We believe this would be absolutely legitimate."
Yet, the Russian government and the interim Ukrainian government have been in contact. "I'd say that they are quite sluggish, but the first steps have been taken," Ukrainian Prime Minister Arseniy Yatsenyuk said. Consultations have been held on the ministerial level.
"Ukraine is ready to build a new style of relations with the Russian Federation," Yatsenyuk said, based on Russia's respect for Ukraine's right to determine its own policies.
Englund reported from Kiev. Washington Post staff writers Carol Morello in Kiev and William Booth in Simferopol, Crimea, contributed to this report.