KIEV, Ukraine (CNN) — NATO Secretary General Anders Fogh Rasmussen on Friday condemned what he called a “serious escalation of Russian aggression” in Ukraine and said Moscow is carrying out direct military operations there.
Accusing Moscow of “hollow denials,” Rasmussen said that Russian troops had illegally crossed the border into Ukraine and that this was not an isolated action but part of a campaign to “destabilize Ukraine as a sovereign nation.”
Rasmussen, who spoke after a meeting of NATO ambassadors in Brussels, Belgium, said Russia’s action was a blatant violation of Ukraine’s sovereignty and “defies all diplomatic efforts for a peaceful solution.”
NATO on Thursday produced what it says are satellite images showing Russian troops engaged in military operations inside Ukraine.
On the same day, a U.S. official accused Russia of sending up to 1,000 of its soldiers into southern Ukraine to fight alongside the rebels. An emergency U.N. Security Council was summoned over the crisis.
Russia continues to deny that it is either supporting the rebel forces or has sent its own forces over the border.
Russian Foreign Minister Sergey Lavrov dismissed the NATO evidence at a news conference in Moscow on Friday.
Referring to past satellite images presented by NATO apparently showing a buildup of Russian forces on Ukraine’s border, he claimed that “it turned out those were images from computer games — the latest accusations are pretty similar.”
Lavrov said no evidence of a purported incursion was presented to Russia, adding, “I do believe that hiding the evidence is an outstanding characteristic of the U.S. and many EU countries” with regards to Ukraine.
Addressing participants at a youth camp Friday, Russian President Vladimir Putin said that Ukrainian authorities need to sit at the negotiating table, “but they speak the language of ultimatums instead.”
A Russian Foreign Ministry statement accused the West of failing to condemn the deaths of civilians in military action by Ukrainian forces, and called for a ceasefire and negotiated settlement of the crisis.
“When Kiev said that negotiations would begin only after the surrender of those whom they call ‘separatists,’ the militia are left with no choice but to defend their homes, their families,” it said.
It also called for the immediate release of Russian Embassy security guards it said were arrested Thursday in Kiev under the pretext that they had grenades.
Earlier Friday, Putin’s office said pro-Russian rebels in Ukraine should open a humanitarian corridor for surrounded Ukrainian troops to retreat from the battlefield.
Ukrainian troops have been fighting on two fronts: southeast of rebel-held Donetsk, and along the nation’s southern coast in the town of Novoazovsk, about 12 miles (20 kilometers) from the Russian border.
Mykhailo Lysenko, the deputy commander of the Ukrainian Donbas battalion, on Thursday described the fighting in the south as “a full-scale invasion.”
Analysts suggest that Russia may have sent its forces into Novoazovsk to secure a land route from the border to the Crimean peninsula it annexed from Ukraine in March, and in order to throw Ukrainian forces making gains against besieged rebel forces in the cities of Donetsk and Luhansk off balance.
In a statement issued by the Kremlin, Putin said the rebels had halted a Ukrainian military operation in eastern Ukraine that he said had endangered the civilian population and caused many casualties.
As a result, he said, they should allow the Ukrainian soldiers to leave the battlefield, in order to reunite with their families, get help for the injured and avoid more casualties.
The Prime Minister of the self-declared Donetsk People’s Republic, Alexander Zakharchenko, said on Russia’s state-run Russia 24 TV channel that the rebels would do so if the surrounded Ukrainian troops agreed to hand over their weapons.
West to consider further sanctions
U.S. President Barack Obama and German Chancellor Angela Merkel agreed in a phone call Thursday that the United States and the European Union would have to consider additional sanctions on Russia.
They also reiterated their determination to continue to work for a diplomatic solution to the crisis, a White House readout of the call said.
Speaking to reporters in Washington, Obama said, “The violence is encouraged by Russia. The separatists are trained by Russia; they are armed by Russia; they are funded by Russia.”
Calling sanctions against Russia already in place “effective,” he said it would face additional consequences for its ongoing incursion. Russia, he added, is “already more isolated than at any time since the end of the Cold War.”
The economic sanctions already imposed against Russian individuals and businesses have had an impact but have also affected some European businesses. Russia has imposed its own sanctions in retaliation for the Western measures.
Russia is a major supplier of natural gas to European nations, complicating efforts to exert pressure on Moscow.
EU foreign ministers are meeting in Italy on Friday and Saturday to discuss the crisis.
NATO: Satellite images show Russian troops
A U.S. official told CNN on Thursday that intelligence now indicates that up to 1,000 Russian troops have moved into southern Ukraine with heavy weapons and are fighting there.
NATO, meanwhile, provided satellite images showing what it said were Russian artillery engaged in military operations inside Ukraine in late August.
Brig. Gen. Nico Tak, a senior NATO commander in Europe, said Thursday that the satellite images “provide additional evidence that Russian combat soldiers, equipped with sophisticated heavy weaponry, are operating inside Ukraine’s sovereign territory” and that the Russians are transferring advanced weapons to the rebels.
“The presence of these weapons along with substantial numbers of Russian combat troops inside Ukraine make the situation increasingly grave,” he said.
Commercial satellite imagery shows the same, according to a British security source with detailed knowledge of UK intelligence estimates. One image that British intelligence has analyzed, dated Tuesday, shows 15 heavy trucks, at least seven armored vehicles and at least nine artillery positions.
Rory Finnin, director of Ukrainian Studies at Cambridge University, told CNN that what’s happening now in Ukraine “is very clearly an invasion — but it’s really the latest in an invasion, as it were, by installments that has been occurring for months.”
Finnin said the Kremlin appeared to have shifted its approach, however.
“Essentially, it’s decided that its geopolitical goals have not been achieved by way of stealth and deception, (nor) by inflating and sponsoring what had been a very marginal separatist movement, so now it is openly using regular Russian forces, openly risking the lives of Russian soldiers and, in fact, a backlash back home.”
U.N. reports abuses, civilian deaths
Heavy fighting in densely populated areas of eastern Ukraine has led to the death and injury of many civilians trapped in urban areas, the Office of the U.N. High Commissioner for Human Rights said.
A new report Friday, covering the month to August 17, said an average of 36 people were killed every day.
“There is an urgent need to end the fighting and violence in the eastern regions, before more civilians are harmed or forced to flee, or face intolerable hardships trapped inside the conflict zones,” said U.N. High Commissioner for Human Rights Navi Pillay.
The report also documents “a wide array of serious human rights abuses” committed primarily by the rebel fighters.
Violations have also been committed by members of the Ukrainian military as they try to recapture rebel-held territory, it said.
At least 2,593 people were killed in Ukraine between mid-April and August 27, it said.
Journalist Victoria Butenko reported from Kiev, and Laura Smith-Spark wrote and reported in London. CNN’s Alla Eshchenko, Elaine Ly and Barbara Starr contributed to this report.