Background: Over the weeks Russia has amassed approximately 190,000 troops near the Ukraine border.

Last week, Russia attempted to downplay those numbers and claim some of the troops have been ordered to withdraw from the area. However, the Biden administration has dismissed those claims as false.

On Sunday, Secretary of State Antony Blinken agreed to meet with Russian Foreign Minister Sergey Lavrov this week, provided Russia does not invade Ukraine, amid a push to de-escalate tensions through diplomacy.

President Biden has also similarly agreed to meet with Russian President Vladimir Putin “in principle” on the condition that the Russian leader does not proceed with an invasion of Ukraine. However, the Kremlin appeared to snub Biden’s offer. [Read Next: Kremlin Snubs Biden Offer of Peace Summit as Invasion of Ukraine Appears Imminent]

What Happened: Sullivan warned that Russia will work to “crush” Ukraine if an invasion happens.

“We believe that any military operation of the size, scope and magnitude of what we believe the Russians are planning will be extremely violent. It will cost the lives of Ukrainians and Russians, civilians and military personnel alike,” Sullivan said during an appearance on NBC’s “Today.”

“But we also have intelligence to suggest that there will be an even greater form of brutality because this will not simply be some conventional war between two armies,” he added. “It will be a war waged by Russia on the Ukrainian people to repress them, to crush them, to harm them.” (per The Hill)

On Sunday, Bathsheba Crocker, U.S. ambassador to the United Nations, sent a letter to the U.N. human rights chief warning that Russia has lists of Ukrainians to be “killed or sent to camps.” (per Fox News)

“I would like to bring to your attention disturbing information recently obtained by the United States that indicates that human rights violations and abuses in the aftermath of a further invasion are being planned,” Crocker wrote. “These acts, which in past Russian operations have included targeted killings, kidnappings/forced disappearances, unjust detentions, and the use of torture, would likely target those who oppose Russian actions, including Russian and Belarusian dissidents in exile in Ukraine, journalists and anti-corruption activists, and vulnerable populations such as religious and ethnic minorities and LGBTQI+ persons.”

“Specifically, we have credible information that indicates Russian forces are creating lists of identified Ukrainians to be killed or sent to camps following a military occupation,” she warned. “We also have credible information that Russian forces will likely use lethal measures to disperse peaceful protests or otherwise counter peaceful exercises of perceived resistance from civilian populations.”

What Comes Next: On Monday, Sullivan reiterated the U.S. is prepared to respond, regardless of how diplomatic efforts pan out.

“We’re prepared to respond decisively if Russia moves on Ukraine and we’re prepared for diplomacy to settle this peacefully, including at the highest level,” Sullivan said. (per The Hill)