The Biden administration has been "weak-kneed" on its response to Russia's threat to Ukraine, rather than enacting sanctions before an invasion that will make Russian President Vladimir Putin "choke on trying to swallow Ukraine," Sen. John Barrasso said Sunday. 

"They've been dragging their feet," the Wyoming Republican, a member of the Foreign Relations Committee and part of a bipartisan group of senators negotiating legislation for sanctions on Russia, said on "Fox News Sunday." "They want Democrats to water it down. We need pressing, biting sanctions now, not after an invasion."

Putin, he warned, is talking about "putting together the old Soviet Union, and Ukraine is the first part of that. He wants to swallow the whole thing, and it is the second-largest country in Europe."

The United States must prevent that from happening "through letting him know that it's going to be very painful if he tries to do it," said Barrasso "If he gets away with it, that's the bigger problem. He needs to choke on trying to swallow Ukraine because if it's easy pickings for him. My worry is that then China moves against Taiwan and Iran moves quickly to a nuclear weapon."

Barrasso also said the meeting between Putin and China's President Xi Jinping at the Beijing Olympics shows the real test of President Joe Biden's resolve will be their apparent willingness to stand in solidarity while being "eager to double-team America."

And, Barrasso said that while he doesn't know if Putin has made a final decision on launching an invasion, it's incumbent on the United States "to do everything we can to discourage him, if he made the decision by himself."

Barrasso was also part of a closed-door intelligence briefing last week, where Joint Chief of Staff Chairman Mark Milley said it is possible that Ukraine's capital, Kyiv, could fall within 72 hours and that a full-scale invasion could cause at least 50,000 Ukrainian casualties.

Putin, said Barrasso, has "made it clear" that he is a "predator."

"If we put biting sanctions in place right now without delay, before an attack, then those will be financial as well as to make sure that Ukraine has the weapons they need to defend themselves," he continued. "That's not U.S. troops. That is Ukraine defending itself with first-class weapons. That will make Putin think twice."

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