United Nations (United States) (AFP) - Washington's envoy to the United Nations told the Security Council Thursday that Russia "must stop lying," accusing Moscow of sending soldiers, tanks and weaponry to support separatists in eastern Ukraine.
The blunt accusation came during an emergency session of the council called after NATO reported that hundreds of Russian government troops had crossed into east Ukraine to shore up the pro-Kremlin fighters.
"Russia has to stop lying and has to stop fueling this conflict," US Ambassador Samantha Power said.
"The mask is coming off. We see Russia's actions for what they are: a deliberate effort to support and now fight alongside illegal separatists in another sovereign country."
NATO said at least 1,000 Russian troops were on the ground supporting the separatists who have been fighting Kiev's rule since April, but Russia again insisted none of its soldiers were on Ukrainian soil.
Russian Ambassador Vitaly Churkin did not offer any direct response to accusations that Moscow had dispatched troops, but said that "US special advisors" were active in Ukraine and called on the United States to "stop interfering" in other countries' affairs.
Churkin put the blame squarely on the Kiev authorities, accusing them of resorting to force instead of seeking a political deal with the separatists.
"The current escalation is a direct consequence of the policies of Kiev," he said.
Power said satellite imagery taken Tuesday, just when Russian President Vladimir Putin met his Ukrainian counterpart Petro Poroshenko, showed Russian combat units southeast of Donetsk, the main rebel stronghold in east Ukraine.
Ukrainian forces detained Russian army personnel in Lugansk, another rebel city, on that same day, whom Moscow later said had wandered into Ukraine by mistake.
"Russia's force along the border is the largest it has been since it began redeploying forces there in late May," Power said, adding that there were "significant numbers" of combat aircraft and helicopters.
- 'Inaction unacceptable' -
The security council was holding its 24th meeting on the Ukraine crisis since April, but the sessions have yielded nothing more than condemnation from the United States and European countries.
Power said it was time to consider taking a stronger stance.
"What message are we sending to other countries with similarly alarming ambitions around the world when we let Russia violate these rules without sufficient consequences?" she asked.
"In the face of this threat, the cost of inaction is unacceptable."
Lithuania's envoy Raimonda Murmokaite, who requested the urgent meeting, denounced an "invasion of Ukraine's territory by the armed forces of the Russian federation" and described it as a "serious blow" to stability across the region and well beyond.
Kiev said Russian troops on Wednesday seized control of the key border town of Novoazovsk and a string of surrounding villages along the southeastern strip of the frontier.
Ukraine's military also claimed a Russian battalion had set up its headquarters near a village in the same area.
UN Secretary General Ban Ki-moon said he was alarmed by reports of fighting in east Ukraine spreading southward.
"If confirmed, this will mark a dangerous escalation in the Ukrainian crisis," said Ban.