The United States and its European allies are planning for "a number of contingencies," fearing that Moscow's saber-rattling may be more than tough talk.
Multiple U.S. officials cited serious concerns Tuesday about what they consistently described as Russia's "unusual military activity" along its border with Ukraine, as well as Moscow's harsh rhetoric, insisting that no matter what happens next, Washington's support for Kyiv is "rock solid."
"We have demonstrated that the United States is willing to use a number of tools to address harmful Russian actions, and we will not hesitate from making use of those and other tools in the future," a senior administration official told VOA on the condition of anonymity in order to discuss the sensitive subject.
"[We] call on Moscow to de-escalate tensions," the official added. "A crucial first step is to restore the cease-fire to the low levels of violence reached in July 2020."
At the State Department on Tuesday, spokesperson Ned Price told reporters Washington's consultations with its European partners, and with Ukraine, are ongoing.
"We are sharing information, we are sharing intelligence," he said, describing the talks as in-depth. "We are prepared and preparing for a number of contingencies."
The comments from the White House and the State Department came just hours after the senior-most U.S. general, Chairman of the Joint Chiefs of Staff Mark Milley, spoke with his Russian counterpart by phone.
The two generals "discussed several security-related issues of concern," the Pentagon said in a statement, adding the call was "a continuation of communication between both leaders to ensure risk reduction and operational de-confliction."
The Pentagon said, per prior agreement, additional details of the call would be kept private.
Tuesday's call between the U.S. and Russia comes after the senior-most U.S. and Ukrainian generals spoke twice within a four-day span to "share perspectives and assessments of the evolving security environment in Eastern Europe."
Ukrainian intelligence estimates have put the number of Russian troops along the border at about 90,000.
U.S. officials have refused to address that figure publicly but called the Russian military buildup along its border with Ukraine worrisome.
"We don't know what Vladimir Putin and the Kremlin might be planning," the State Department's Price told reporters.
"We do know the history and that history is not at all reassuring," he added, pointing to Russia's invasion of Crimea in 2014.
Price also rebuffed recent Russian criticism of U.S. military drills in the region, saying the U.S. and its allies would continue to stand up the "rules-based international order."
Russian TASS news agency quoted Russian Defense Minister Sergei Shoigu as saying Moscow was "witnessing a considerable increase in the U.S. strategic bombers' activity near the Russian borders."
Shoigu also alleged U.S. strategic bombers "practiced employing nuclear weapons against Russia actually simultaneously from the western and eastern directions."
A day earlier, Russia's Foreign Intelligence Service, the SVR, likewise criticized the U.S., posting on its website that the current situation with Ukraine is comparable to tensions with Georgia prior to the 2008 Russian invasion, noting Georgia paid a high price.
The U.S. has provided Ukraine with $2.5 billion in security assistance since 2014, including $400 million in 2021 alone.
Recent deliveries include patrol boats for the Ukrainian navy and 80,000 kilos of ammunition for Ukrainian forces.