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Charles Krauthammer said Russian President Vladimir Putin is a "KGB agent" and a "liar," and would never admit to meddling in the U.S. presidential election.

It was "farcical" to think light would be shed on Russia's interference in the election at Friday's G-20 Summit, the columnist said.

"What was important is that our president would say, 'We know what you did. Don't do it again or you're going to suffer, and we don't have to say what it's going to be.'"

President Trump and President Putin held a long-anticipated two-and-a-half hour meeting in Germany Friday, where they discussed Syria and Russia's interference in the U.S. 2016 presidential election.

A dispute about what Trump and Putin actually said to one another broke out later Friday after Russian Foreign Minister Sergey Lavrov insisted President Trump had accepted Putin's claims that Russia did not interfere in the U.S. election.

"I don't believe a word of the Russian readout," Krauthammer added.

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The Syria issue was the only one that had potential for progress at the Friday meeting, he said.

Krauthammer said the cease-fire negotiated in Syria will be productive, and is similar to 1945 post-war boundaries negotiations. He added that a major goal should be to prevent Iran from taking over vulnerable territory.

Krauthammer said his only concern was the possible presence of Russian military police in Syria during the cease-fire.

"We have no business allowing them in this region," he stated.

"We have to see them as an adversary," Krauthammer said of Russia.

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