Ukrainian President Petro Poroshenko warned that his nation's crisis with Russia has worsened in recent days and is inching closer to a "full-scale war."
"I think we are very close to the point of no return," Petro Poroshenko said Saturday following an EU summit in Brussels. "The point of no return is full-scale war, which already happened in the territory controlled by separatists and where -- instead of separatists -- there are regular Russian troops."
Poroshenko said thousands of foreign troops and hundreds of foreign tanks are now on Ukrainian territory.
Russia has repeatedly denied supporting the rebels or sending troops over the border. But the West has rejected Moscow's denials.
European Council President Herman Van Rompuy, speaking at a meeting in Brussels, said new sanctions are in the works for Russia.
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"The European Council says that it stands ready to take further significant steps in the light of the evolution of the situation on the ground and it requests the commission to urgently undertake preparatory work ... and present proposals for consideration within a week," Rompuy said.
As condemnation from the West escalated, Russian President Vladimir Putin appeared defiant.
Moscow doesn't want or intend to wade into any "large-scale conflicts," Putin said, according to state-run Itar-Tass. A few breaths later, he said Russia is "strengthening our nuclear deterrence forces and our armed forces," making them more efficient and modernized.
"I want to remind you that Russia is one of the most powerful nuclear nations," Putin said. "This is a reality, not just words."