KYIV, Ukraine — It's hard to imagine higher stakes than the ones right now for the U.S. charge d'affaires, who is currently the top American official on the ground in the Ukrainian capital of Kyiv.
This week, with all eyes on the Russian border, Kristina Kvien is juggling talks with fellow diplomats and visiting members of Congress.
Her current estimate is Russian President Vladimir Putin has more than 100,000 troops at the border to Ukraine, and that number is growing.
"The troop buildup is continuing. It's not continuing at a rapid pace, but it is continuing at a regular pace," Kvien told NPR's All Things Considered.
Asked how concerned she is about the prospect of an imminent invasion, Kvien's response was simple: "We are very concerned."
"First of all, the number of troops and materiel that the Russians have at the border could allow them to do some sort of incursion at any time," she said. "So, when President Biden says that action is imminent, it's because there are enough now to do some sort of action."
Kvien is confident that if that were to happen, Ukraine's military would put up a significant fight. They are well-trained, well-equipped and very motivated, she said.
"Ukrainians in general and the Ukrainian military are very patriotic. They love Ukraine. They're willing to fight to save it. And I anticipate that they would do so and they would do so with great vigor."
While the situation appears to be a deadlock, with the U.S. steadfast in its refusal to Russia's demand that Ukraine never be allowed to join NATO, Kvien is still hopeful a diplomatic solution is on the table.
The choice remains with Russia, she said.
"They have two paths they can take. The first, which is obviously the one that we and the Ukrainians very strongly prefer, is the path of diplomacy and discussion. The other path is the path of Russian aggression. And make no mistake about it, if Russia takes the path of aggression, it will face extremely severe consequences immediately."
"We have arrayed a group of sanctions and export controls that would have a very severe impact on Russia's economy, and we would implement those the moment that Russia takes aggressive action against Ukraine."
This is a message two visiting U.S. congressmen can get behind.
Gregory Meeks, D-N.Y., and Mark Green, R-Tenn., are both members of the U.S. House Foreign Affairs Committee and are in Kyiv.
They say while sanctions — and whether they are implemented before or after any invasion — remain an ongoing discussion, what is most important now is unity among Ukraine and its allies.
"Because the way Putin wins, is if he can divide us," Meeks said. "He would love to divide some of our NATO allies and some of our EU allies, and Ukrainians, divide us on this issue, that would be a victory for him. So we can't allow that to happen."
Green agreed, and said the calculation for the United States was an easy one.
"[Putin] put troops on the border of a NATO ally. And that changes the game for me. ... We're compelled to work to a diplomatic solution here as quickly and as effectively as we can," he said.
As for what to look for next, Kvien said the U.S. was preparing for any moves and was waiting to hear from Putin himself.
"When taking information from Russia, frankly, it's President Putin you need to listen to, and he hasn't spoken yet, so we're waiting for him to speak out," she said. "We're hoping that he does choose a diplomatic path. If he does, I think we have a lot of things we can talk about."
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