Sen. Chris Van Hollen (D-Md.) said the summit between President Donald Trump and Russian President Vladimir Putin was "a bad day for the United States" because Trump refused to hold Putin accountable for Russian interference in the 2016 U.S. election.

Putin, emphatically and repeatedly, denied meddling in the U.S. election during a press conference after the summit, saying there's "no evidence."

Trump was criticized by many for not pressing Putin on the point and seemingly siding with the Russia president over the American intelligence community, which claims Moscow meddled in the election.

"He threw our intelligence community totally under the bus and said, 'Hey, I have no reason to doubt Vladimir Putin,'" Van Hollen said on "Outnumbered Overtime." "This is a crazy, upside-down world, which is why you have such strong responses not just from Democrats but from Republicans as well."

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He added that Trump also failed to call out other Russian aggressions, including their annexation of Crimea and support of Syrian dictator Bashar Assad.

He said if former President Obama emerged from a meeting with Putin praising the Russian president and declining to side with the U.S. intelligence community, there would be a "huge uproar" from Republicans.

"I am pleased to say that there are at least some Republican senators who are joining Democrats in criticizing the president's actions here," Van Hollen said.

Watch the "Outnumbered Overtime" clip above, and see how other Democrats reacted to the summit.

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