Kim Hjelmgaard

USA TODAY

MUNICH, Germany — Russian Prime Minister Dmitry Medvedev told a security conference here Saturday that the world was in a new Cold War and that the West was to blame.

"NATO's attitude toward Russia remains unfriendly and opaque, and one could go so far as to say we have slid back to a new Cold War," Medvedev said.

"Sometimes I wonder if it is the year 2016 or 1962," he said.

Medvedev made the comments during an appearance at the Munich Security Conference, a high-level event attended by dozens of world leaders and senior diplomats. This year's participants include U.S. Secretary of State John Kerry, French Prime Minister Manuel Valls, Ukrainian President Petro Poroshenko, Russian Foreign Minister Sergey Lavrov, and many others.

Medvedev said the sanctions imposed on Russia by the West after Moscow's annexation of Crimea and new military moves by the NATO alliance were aggravating tensions. At the same conference in 2007, Russian President Vladimir Putin said the West’s building of a missile defense system risked restarting the Cold War.

“The picture is more grim" than in 2007, Medvedev said.

His remarks came after NATO Secretary General Jens Stoltenberg used an address to defend NATO’s move to strengthen its defenses, including moving more troops and equipment to countries bordering Russia. Stoltenberg said he expected a summer NATO summit in Warsaw would be used “to decide to further strengthen the alliance’s defense and deterrence.”

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“Russia’s rhetoric, posture and exercises of its nuclear forces are aimed at intimidating its neighbors, undermining trust and stability in Europe,” he said.

In a separate panel, Poroshenko made an emotional appeal for continued support for his country amid its conflict with Russia in eastern Ukraine. A 1-year-old peace deal — the Minsk agreement — has not been fully implemented.

Both sides accuse each other for that failure.

"I am a president of a country that is in a state of war, and I want to give you one important fact: You can run my country only if you are an optimist. If you are a pessimist you will lose, and lose the country," he said. "We strongly put our trust in European unity, in transatlantic unity, and in solidarity in Ukraine."

"Exactly two years ago hundreds of Ukrainians gave their lives because of their dreams to live in Europe," he said.

February 22 marks the two-year anniversary of former Ukraine President Viktor Yanukovych's ousting, in part because he failed to sign a deal with the European Union that would lead to closer cooperation. Yanukovych fled to Russia.

Frank-Walter Steinmeier, Germany's foreign minister, said he was “counting on it being clear to all those in positions of responsibility in Kiev and Moscow that we no longer have forever to implement what was agreed in Minsk."

Kerry used his speech to praise European nations for holding firm on Ukraine-related sanctions against Russia. Following Friday's deal that might lead to a cease-fire in Syria, he said it was time for Moscow to act in good faith in forging a truce.

Referring to the ongoing conflict in Syria, Medvedev denied that his country is killing civilians as its military conducts airstrikes in support of Syrian President Bashar Assad. "Everyone is accusing us of this. It's not true," Medvedev said.

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