The Ukraine crisis is the classic case of a known unknown: We know that we don’t know what Russian President Vladimir Putin intends to do as he amasses troops on the Ukrainian border.
So how imminent is the threat of a full-scale war? Some fears appear to have receded slightly following key talks that included Russian and Ukrainian officials. But the Pentagon also says the Russian troop buildup continues, and President Joe Biden told his Ukrainian counterpart Volodymyr Zelensky on a call Thursday that there was a distinct possibility Russia could launch an invasion in February, according to National Security Council Spokesperson Emily Horne.
Zelensky, however, restated his position that the threat from Russia remains “dangerous but ambiguous,” and it is not certain that an attack will take place, a senior Ukrainian official told CNN. Diplomatic efforts to defuse the crisis continue.
Taking that into account, here’s a look at how soon an invasion could happen and what it might look like.
How imminent is the threat of war really?
Analysts say Russia has a menu of options to attack at any moment it chooses, from shock-and-awe style air strikes to a ground invasion along a broad front. But while it has moved large amounts of military equipment into place in areas bordering Ukraine, not all the personnel needed for a ground operation are ready.
“At the moment, Russia has a lot of equipment pre-positioned along with its own border with Ukraine,” said Janes, a global agency for open-source defense intelligence. “(This) reduces the amount of time it requires for them to fill that area with more forces if they decide to fight because all of their heavy equipment’s there.”
Troops can be deployed in less than 72 hours, the agency said, since they need only be sent from their bases by plane or train across the country.
Russia is also in the process of deploying “quite a sizable formation” in Belarus from its Eastern Military District (EMD), which extends from Russia’s Pacific Coast to Siberia, Janes said. This formation, which Janes first detected moving west early this month, appears to include troops, logistics and communications resources as well as military equipment.
Russia has said the force is there for a Russian-Belarusian training exercise. But according to Janes, the troops “are essentially deploying as close to ready to go as you can be.”
Judging by what has been pre-positioned on Russian soil near Ukraine’s border, it considers Russia would require “maybe a maximum of two weeks of intense movement to bring all of the pieces into position” if it were to launch an invasion.
Whether Russia would want to put large numbers of boots on the ground remains unclear, particularly given the risk of casualties.
“The important thing to realize is that (Russia) is quite wary of what it calls contact warfare,” that is, forces fighting each on the ground, said Sam Cranny-Evans, a research analyst with the UK-based Royal United Services Institute (RUSI). “We’ve seen (this) in Chechnya, in Afghanistan, in Georgia and its covert deployments to Ukraine, that military losses actually do generate political pressure.”
Russia could instead opt to use its very long-range intelligence, surveillance and reconnaissance assets to target critical national infrastructure within Ukraine, such as military bases or even power plants and bridges, Cranny-Evans said. “The goal is to either stop a contact conflict from emerging or shape the battlefield so that when one does emerge, it’s much more favorable to the Russian forces,” he said.
US intelligence findings in December estimated that Russia could begin a military offensive in Ukraine “as soon as early 2022.” Since then, US officials have stuck to that line.
However, Ukrainian officials say the latest military intelligence suggests Russian forces are not yet prepared to stage a full-blown invasion into the country.
Speaking to CNN on Tuesday, a source close to the Ukrainian leadership said defense and intelligence chiefs were analyzing satellite images of Russian forces “from US and other western agencies” on an hourly basis, but were not yet seeing Russia “getting into combat mode, or positioning themselves to attack.”
Ukrainian intelligence assesses that the threat from Russia is “dangerous, but not imminent,” the source told CNN, and that if any Russian order to attack were given it would still take one to two weeks for Russian forces near the border to be ready.
Ukraine’s Foreign Minister Dmytro Kuleba struck a similar note Wednesday, saying Russian troops could attack Ukraine at any time, as had been the case since 2014, but that its forces were not yet fully assembled. “We can say 100 times a day invasion is imminent, but this doesn’t change the situation on the ground,” he said.

“In terms of timelines, what we’ve seen up until now has been very overt signaling of the intention for the ability to invade Ukraine,” said Cranny-Evans. But the Russians are “taking their time” to get the final pieces into place in order to leave space for conversations which might allow them to achieve their political goals, such as installing a pro-Kremlin or even neutral leader in Kiev, without having to fight, he suggested.
If it does come to an invasion, he considers that Russia could move the necessary troops into place in the space of 72 hours. “It’s the forces that Russia already has in the Southern Military District on the borders with Ukraine that would probably take on the first bit of fighting,” Cranny-Evans said.
The Kremlin denies it is planning to attack and argues that it is NATO’s support for Ukraine – including increased weapons supplies and military training – that constitutes a growing threat on Russia’s western flank.
What else could influence the timeline for a potential invasion?
There may also be non-geopolitical factors to take into account, such as the weather and the upcoming Winter Olympics in Beijing.
If Putin orders his forces to invade, some analysts have speculated it would come before the spring thaw. “The best time to do it is winter because it’s going to be a mechanized advance and the mechanized divisions need hard frozen ground,” journalist and author Tim Marshall told CNN.
Howe