Tensions between Washington and the Kremlin have reached a boiling point not seen since the Cold War as over 100,000 Russian soldiers have amassed along the border over the last several months.
NATO member nations have repeatedly warned the Kremlin that should it invade its neighbor to the west, there would be serious repercussions, including severe economic sanctions.
In contrast to his language earlier in the week, Putin on Thursday alleged he does not want confrontation with Ukraine but said he needs security guarantees from the West that the former Soviet nation will not be permitted to join NATO.
"You must give us a guarantee. And immediately — now," Putin said during a four-hour-long press conference.
Putin claimed that should Kyiv be able to join NATO, "bases and strike weapons systems" could be placed in Ukraine and would pose an additional threat to the Kremlin.
"It presents an ultimate threat to Russia because the flight time of missile strikes will be reduced to seven to 10 minutes, and it's simply not enough time to react," former Defense Intelligence Agency (DIA) intelligence officer for Russian doctrine and strategy, Rebekah Koffler, told Fox News.
But Koffler argued Putin has another motive for threatening to invade Ukraine.
"He softened the language a little bit," the former DIA officer said comparing the Thursday presser to unfounded accusations made earlier in the week.
"They want to create a tactical prize, they want to keep us guessing, they want to keep us on edge," Koffler, who authored "Putin's Playbook: Russia's Secret Plan to Defeat America," said. She added that Putin is assessing the Biden administration to see if there is "a change in force posture."
Koffler warned that Putin’s recent language echoes comments made in the lead up to the 2014 invasion of Ukraine and said she believes there could be an invasion as soon as Christmas Eve.
"He understands that we, our intelligence agencies, and national security apparatus are going to operate on a skeleton crew — he is more likely to achieve tactical surprise," she warned.
Koffler said she believes the threat of invasion remains the highest through mid-January, explaining that security agencies in Ukraine could be operating at reduced capacities as the Eastern Orthodox Church celebrates Christmas on Jan. 7, according to the old Julian calendar.
But another defense expert pointed documents obtained by intelligence officials earlier this month that suggested the threat may actually be highest from late January to February, explained American Enterprise Institute senior fellow and director of the Critical Threats Project, Fred Kagan.
"Putin is clearly setting conditions to be able to invade, to conduct a full-scale invasion of Ukraine this winter," Kagan said.
The foreign policy expert said that Russia views the expansion of NATO as a "pressure campaign" and is using the threat of a Ukraine invasion as a bargaining chip to deny the former Soviet state access to the Western alliance.
"He’s making this a crisis," former CIA Moscow station chief Dan Hoffman told Fox News in reference to Putin. "He’s portraying Ukraine as the aggressor. He’s saying that the Russian motherland is under threat — it’s all typical Soviet propaganda."
Both Hoffman and Kagan said they did not believe a Russian invasion of Ukraine was imminent but warned it remained a possibility as long as Putin continues to mass troops on the border.
"Putin is doing all of this for leverage," Hoffman said. "And he knows if we do agree not to allow Ukraine to join NATO or to give Russia some veto power over it — we have wrecked Ukraine’s democracy."
Washington and Moscow are set to hold talks in the New Year to negotiate Russia's security demands.