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Nato told Russia it is not too late to “step back from the brink” at a time of heightened tensions over Ukraine and prevent war in eastern Europe.
Jens Stoltenberg, the head of Nato, insisted that the military alliance was ready to “engage in a substantive dialogue” with Russia to address its security concerns, reduce the threat of conflict in Ukraine and find common ground.
But the Nato chief said that there were no signs of a Russian troop withdrawal from its border with Ukraine, despite claims to the contrary from Moscow.
“On the contrary, Russia's military build-up continues,” Mr Stoltenberg told the Munich Security Conference.
The US said that Russia has as many as 190,000 soldiers on its border with Ukraine, leading to fears in many western capitals that an invasion is imminent.
Moscow issued a series of security demands to Nato, many of which were rejected out of hand, while diplomatic efforts to calm tensions made little progress.
Russia denies it is planning to invade Ukraine and accuses Nato of provocation.
“These are dangerous days for Europe. Russia has relentlessly massed troops in the biggest military build-up since the Cold War. We do not know what will happen but the risk for conflict is real,” Mr Stoltenberg said.
“We call on Russia to do what it says and withdraw its forces from the borders of Ukraine. This will be an important first step towards a peaceful solution. It is not too late for Russia to change course, to step back from the brink, stop preparing for war, and start working for a peaceful solution.”
Russia has demanded that Nato withdraw its troops from Eastern Europe – including former Soviet states – and stop Ukraine from joining the military alliance. Both proposals were rejected by Nato.
Mr Stoltenberg said in Munich that there was no such thing as “first-class members” of Nato in the west of the alliance, and “second-class members” to the east.
German Chancellor Olaf Scholz said the West was ready to negotiate over Russia's security demands “without being naive".
“We will differentiate clearly between untenable demands and legitimate security interests,” he said.
Also speaking in Munich was European Commission President Ursula von der Leyen, who told Moscow that its thinking from “a dark past” could cost Russia a prosperous future.
“The world has been watching in disbelief as we face the largest build-up of troops on European soil since the darkest days of the Cold War, because the events of these days could reshape the entire international order,” she said.
