Russian President Vladimir Putin has compared Ukraine to Nazis, saying the country's Friday request to join NATO and regain control of its eastern cities is akin to the Nazi invasion of the Soviet Union in World War II.
Speaking to young people at a summer camp, Reuters reported, Putin told his countrymen they must be "ready to repel any aggression towards Russia." He described Ukrainians and Russians as "practically one people," language that Ukrainians say dismisses the very existence of their thousand-year-old nation.
The past 72 hours have seen pro-Russian rebels suddenly open a new front and push Ukrainian troops out of a key town in strategic coastal territory along the Sea of Azov. Kiev and Western countries say the reversal was the result of the arrival of armoured columns of Russian troops, sent by Putin to prop up a rebellion that would otherwise have been near collapse.
Rebels said they would accept Putin's proposal to allow Kiev forces, who they say are surrounded, to retreat, provided the government forces turn over weapons and armour. Kiev said that only proved that the fighters were doing Moscow's bidding.
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Russia drew a fresh rebuke from French Foreign Minister Laurent Fabius, who told French television station France 24 that Russia could face more sanctions from the European Union.
"When one country sends military forces into another country without the agreement and against the will of another country, that is called an intervention and is clearly unacceptable," he said.
In Washington, White House spokesman Josh Earnest said Russia's footprint was undeniable in Ukraine.
"We have regularly marshaled evidence to indicate what exactly is happening, despite the protestations of the Russian government that for some reason would have us all believe otherwise," he said. "The fact is, those denials are completely without any credibility, and, you know, we've been pretty candid about that."
Full Ukrainian membership of NATO, complete with the protection of a mutual defence pact with the United States, is still an unlikely prospect. But by announcing it is now seeking to join the alliance, Kiev has put more pressure on the West to find ways to protect it. NATO holds a summit next week in Wales.
NATO Secretary General Anders Fogh Rasmussen said he respected Ukraine's right to seek alliances.
"Despite Moscow’s hollow denials, it is now clear that Russian troops and equipment have illegally crossed the border into eastern and southeastern Ukraine," Rasmussen said. "This is not an isolated action, but part of a dangerous pattern over many months to destabilise Ukraine as a sovereign nation."
Kiev said it was rallying to defend the port of Mariupol, the next big city in the path of the pro-Russian advance in the southeast.
"Fortifications are being built. Local people are coming out to help our troops, to stop the city being taken. We are ready to repel any offensive on Mariupol," military spokesman Andriy Lysenko said.
So far, the West had made clear it is not prepared to fight to protect Ukraine but is instead relying on economic sanctions, first imposed after Russia annexed Ukraine's Crimea peninsula in March and tightened several times since.
Those sanctions seem to have done little to deter Putin, leaving Western politicians to seek tougher measures without crippling their own economies, particularly in Europe which relies on Russian energy exports.
European foreign ministers met in Milan on Friday ahead of a weekend EU summit. They made clear the bloc will discuss further economic sanctions against Moscow. Some said that was no longer sufficient, and other measures to help Kiev should be discussed.
Polish Foreign Minister Radoslaw Sikorski said countries that had tried so far to mediate now needed to explain "what their ideas (are) to stop President Putin and save Ukraine as she is". Sweden's Carl Bildt said: "Sanctions alone are not enough: he (Putin) is prepared to sacrifice his own people."
Poland denied permission for Russia's defence minister to fly over its air space after a trip to Slovakia, forcing him to return to Bratislava. Warsaw said he could fly if he reported the status of his plane as civilian rather than military.
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