"Glad-handing with Vladimir Putin on the heels of these indictments would be an insult to our democracy", Chuck Schumer, Senate Minority Leader, said. John McCain of Arizona, a frequent Trump critic and a Russian Federation hawk, called on the president to cancel the summit if he is "not prepared to hold Putin accountable".
Some Democrats echoed McCain's call for Trump to challenge Putin over election meddling, particularly now that he is armed with information from the latest Mueller indictment.
After taking a firm stance both days of the conference, which included calling Germany a "captive" of Russian energy, Trump did say US commitment to North Atlantic Treaty Organisation remains strong and he thanked other members for "additional money they are putting up".
Democrats railed against Trump's European tour, and said they were wary of the upcoming, one-on-one meeting with Putin.
On Twitter, he said Putin was not America's friend, he was the nation's enemy. "I don't think we have a lot to say to President Putin", Rosenberg told CBN News Middle East Bureau Chief Chris Mitchell.
He said the presidents would meet one on one with just their interpreters. "You know, he's done so well in his negotiations", he said, "I'm not about to second-guess how he's doing it".
"The Russian president is a man schooled in treachery and espionage".
"President Trump should cancel his meeting with Vladimir Putin until Russian Federation takes demonstrable and transparent steps to prove that they won't interfere in future elections", said Senate Democratic leader Chuck Schumer.
"I think it's very sad when Germany makes a massive oil and gas deal with Russia where - we're supposed to be guarding against Russia and Germany goes out and pays billions and billions of dollars a year to Russia", Trump said.
"I think by and large [Putin] views the world as a zero-sum game, but he most certainly views the relationship with the United States and Russian Federation as a zero-sum game", Sen.More news: U.S. threatens sanctions to the participants of Nord stream-2
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He said the Cold War had ended a long time ago, and that in some areas, such as global security, arms control, and fighting worldwide terrorism, Russian and US interests coincided.
President Donald Trump took a victory lap Thursday before leaving the North Atlantic Treaty Organisation summit, referring to himself as a "stable genius" and taking credit for securing a commitment from allies to increase their share of defense spending, a point he constantly drove home during the talks in Brussels.
Donald Trump had hoped to get out of his summit with Vladimir Putin, Robert Mueller changed the game.
Prosecutors also detailed a second Russian operation targeting the infrastructure that Americans use to cast their ballots and the officials that oversee those elections locally.
She said Trump raised the topic of better burden-sharing and more spending by Germany, "as has been discussed for months", and that "we made clear that we're on the way".
The grand jury indicted 12 Russian military intelligence officers on charges they hacked into Hillary Clinton's campaign and the Democratic Party, releasing tens of thousands of stolen and politically damaging communications.
The ministry says "obviously, the objective of this is to spoil the atmosphere" before Monday's summit of President Vladimir Putin and President Donald Trump.
He said that was counterproductive to efforts to pressure Russian Federation. "Anything you do, it's always going to be, 'Oh, Russia, he loves Russia"'.