Washington (CNN) Senate Minority Leader Chuck Schumer called on Republican colleagues to join in "demanding testimony" from President Donald Trump's national security team present during the Helsinki summit earlier this week, including Secretary of State Mike Pompeo, "immediately."

"And very importantly, probably most importantly, our Republican colleagues need to join us in demanding testimony from the President's national security team that was in Helsinki -- and we need to do that immediately," the New York Democrat said from the Senate floor Tuesday.

Schumer said the American people need more information on anything Trump promised Russian President Vladimir Putin, following a press conference Monday where Trump appeared to downplay the US intelligence community's assessment that Russia interfered with the last US presidential election and that Trump said Putin was "extremely strong and powerful" in his denial of responsibility.

"We need hearings as soon as possible to assess what President Trump might have committed to President Putin in secret," Schumer said. "President Trump's public statements were alarming enough."

"Does anyone believe he was tougher on Putin in secret?" Schumer asked. "You can't assume anything but that as weak as he was in public before President Putin, he was even worse in private. Why else did he not want anyone in the room?"

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