“We’ll be fully surrounded by equal forces,” the senior Ukrainian security official said.
In Washington, U.S. officials say they still assess that Mr. Putin has not yet made a decision to invade. They describe him as more a tactician than a grand strategist, and they believe that he is constantly weighing a host of different factors. Among them is how well he could weather the threatened sanctions on his banks and industry, and whether his demands that Ukraine stop veering toward NATO — and that NATO stop spreading toward Russia — are receiving enough attention.
But the U.S. officials say Mr. Putin may also have concluded that with the United States and other countries arming Ukraine, his military advantage is at risk of slipping away. Britain’s defense secretary, Ben Wallace, announced in an address to Parliament on Monday that the country would begin providing Ukraine with light, anti-armor defensive weapons. Mr. Putin may become tempted to act sooner rather than later.
U.S. officials saw Russia’s embassy evacuations coming. “We have information that indicates the Russian government was preparing to evacuate their family members from the Russian Embassy in Ukraine in late December and early January,” a U.S. official said in a statement.
Ukrainian officials say they saw the Russians leave.
But that leaves open the question of what, if anything, the Russians were signaling.
It is possible they were trying to bolster the case that the United States and its Western allies should take seriously their demands that Ukraine can never join NATO, and that troops, nuclear weapons and other heavy weaponry must be removed from former Warsaw Pact states, like Poland, that were once allied with the Soviet Union.
It could also be that the Russians were trying to indicate that an attack was brewing, though there were no other signals. In fact, the buildup of Russian troops on the Ukrainian border is not increasing at a rate that Pentagon officials expected a month ago.
The latest U.S. estimates are that about 60 battalion tactical groups, known as B.T.G.s and each with an average of 800 soldiers, are now in place at the border with Ukraine. Combined with other local forces, the Russians have about 77,000 troops at the border, with more on the way. Others put the figure at closer to 100,000 — much depends on how different forces are counted — but that is well short of the Pentagon’s estimate more than a month ago that the total number could rise to 175,000.