US Secretary of State Antony Blinken on Sunday said Russia had to choose between dialogue and confrontation, ahead of talks in Geneva on soaring tensions over Ukraine.
"There's a path of dialogue and diplomacy to try to resolve some of these differences and avoid a confrontation," Blinken told CNN's "State of the Union" show.
"The other path is confrontation and massive consequences for Russia if it renews its aggression on Ukraine. We are about to test the proposition about which path President Putin is prepared to take."
Vladimir Putin's government has reportedly massed tens of thousands of military troops along Russia's border with Ukraine, drawing Washington into a Cold War-style stand-off.
Blinken warned that any positive outcome from the talks would rely in part on Russia's willingness to stand down from its aggressive posture, which he likened to "an atmosphere of escalation with a gun to Ukraine's head."
"So if we're actually going to make progress, we're going to have to see de-escalation, Russia pulling back from the threat that it currently poses to Ukraine," US President Joe Biden's top diplomat said.
On Sunday Moscow ruled out any concession at the highly anticipated talks, which open a week of diplomacy in which Russian officials will meet with NATO and the Organization for Security and Cooperation in Europe (OSCE).
The Kremlin, wary of NATO's potential eastward expansion, has insisted the grouping never grant membership to Ukraine, a former Soviet state which is pushing to join the trans-Atlantic body.
Washington has also acknowledged that Moscow has expressed interest in discussing the future of missile systems in Europe.
Blinken made the Sunday talk show rounds playing up the need for dialogue.
He acknowledged he was not anticipating major breakthroughs in the talks, but stressed there were potential punishments awaiting Washington's rival if it does not engage in diplomacy.
Russia could face severe economic and financial consequences, "as well as NATO almost certainly having to reinforce its position near Russia as well as continuing to provide assistance to Ukraine," he told ABC's "This Week."
"This is not just me saying it. We have had the G7 (Group of Seven leading democracies) make clear there would be massive consequences. The European Union and NATO partners and allies as well."
Earlier this month Biden told Ukrainian President Volodymyr Zelensky that Washington and its allies would "respond decisively" if Russia moves to invade.