Senate Majority Leader Mitch McConnell | Aaron P. Bernstein/Getty Images Republicans denounce Trump’s defense of ‘killer’ Putin Senate Majority Leader Mitch McConnell said Russian president is ‘a thug.’

Donald Trump’s defense of Vladimir Putin’s homicidal history isn’t sitting well with fellow Republicans.

Three Republican senators and several other conservatives were quick to condemn or distance themselves from the president seeming to put Putin on equal standing with the United States when it comes to killing.

In a pre-taped Fox interview partially released on Saturday and set to air in full during the Super Bowl pre-game show, Bill O’Reilly pressed Trump on his warm relationship with Putin.

Trump stressed that stronger U.S.- Russia ties could help defeat the Islamic State.

But “Putin’s a killer,” O’Reilly said.

“You got a lot of killers,” Trump shot back. “What, you think our country’s so innocent?”

Trump’s repeated expressions of admiration for Putin was already a sore spot for Republicans who consider the Russian leader a threat to the post-World-War-II global order. The president's latest statement has put the breach right back in the spotlight.

“He’s a thug,” Senate Majority Leader Mitch McConnell (R-Ky.) said of Putin on CNN’s “State of the Union.” “The Russians annexed Crimea, invaded Ukraine and messed around in our elections. No, I don’t think there’s any equivalency between the way the Russians conduct themselves and the way the United States does.”

When host Jake Tapper responded that Republicans would have been in revolt if Barack Obama said something similar, McConnell, who’s made a point of not harshly criticizing Trump, made clear his opinion on the matter.

“I’m not going to critique the president’s every utterance," the Senate leader said. "But I do think America is exceptional, America is different. We don’t operate in any way the way the Russians do. I think there’s a clear distinction here that all Americans understand and I would not have characterized it that way.”

Was McConnell confident that Trump understood? Tapper asked. “I obviously don’t see this issue the same way he does,” McConnell replied.

The Republican leader wasn’t alone in his discomfort.

“When has a Democratic political activists been poisoned by the GOP, or vice versa? We are not the same as #Putin,” Sen. Marco Rubio (R-Fla.), a Russia hawk, tweeted Sunday.

And Sen. Ben Sasse (R-Neb.), a persistent Trump critic throughout and since the election season, had a similar take.

“Putin is an enemy of political dissent. The U.S. celebrates political dissent and the right for people to argue free from violence about places or ideas that are in conflict,” Sasse said on ABC’s “This Week.” “There is no moral equivalency between the United States of America, the greatest freedom living nation in the history of the world and the murderous thugs that are in Putin's defense of his cronyism.”

Some conservative writers were more blunt.

“Trump puts US on moral par with Putin's Russia,” the Wall Street Journal’s Bret Stephens tweeted. “Never in history has a President slandered his country like this.”

Vice President Mike Pence was forced to play cleanup on NBC’s “Meet the Press.”

Asked if Trump was creating a “moral equivalency,” Pence said: “No, not in the least.”

“President Trump has been willing to be critical of our country’s actions in the past. But what you’re hearing there is a determination by the president of the United States to not let semantics or the arguments of the past get in the way of exploring the ability to work together with Russia and with President Putin in the days ahead.”

Pence was pressed by host Chuck Todd whether Trump was essentially saying Putin is “a bad guy, but we've done some bad things, too.”

“Again, I don't accept that it's a moral equivalency,” Pence said. “I really don't, Chuck.”