Russia-Ukraine updates: US to ban Russian carriers from its airspace

The Russian military released more videos on Wednesday morning purportedly showing troops pulling back from Moscow-annexed Crimea.

The footage aired on Russian state media, with one video showing a trainload of armour being carried across the Russian-built bridge that connects the Russian-controlled Crimean Peninsula to Russia's mainland. Another video shows military trucks driving out of Crimea across the bridge, which Russian state media described as support troops leaving "exercises."

However, officials in the West and regional analysts continue to caution that they have not yet seen significant movements of Russian troops pulling back from near Ukraine's borders.

Meanwhile, massive military exercises continue in neighboring Belarus and are not due to finish until Sunday. Belarusian Minister of Foreign Affairs Vladimir Makei said Wednesday that "not a single" Russian soldier will remain in the country once those drills end.

-ABC News' Patrick Reevell

Ukrainian President Volodymyr Zelenskyy wished citizens "a happy day of unity" on Wednesday.

Zelenskyy had said on Monday evening that instead of Feb. 16 being "the day of the attack," he would make it "the day of unity" and declared an impromptu national holiday. ABC News has learned that Russian President Vladimir Putin had told his military forces to be ready to invade Ukraine by Wednesday, but it remains unclear whether he has made a decision to attack the neighboring country.

"We are all united by our wish to live, to live in peace, to live a happy life with our families, parents and children. We have the full right to all of this, because we're at home here, in Ukraine," Zelenskyy said in an address on social media Wednesday morning. "Nobody will love our home as much as we do, and nobody can defend our home as we can. I wish you a happy unity day, my blue-yellow ones, a happy day of unity of Ukraine, in the east and west, in the south and north. It works only together, and when it works, we're strong."

As Russia's defense ministry said Tuesday that some forces would pull back from Ukraine's borders after completing military exercises, sources told ABC News that there are troops moving forward closer to the line, including with medical supplies, and being put into firing positions.

The U.S. believes that Russia now has all the necessary pieces in place, including 150,000 troops in the region, to launch a swift and brutal invasion of Ukraine, the sources added -- the reason why Biden administration officials have now publicly been saying Russia could move "at any time."

ABC News has learned that Russian leader Vladimir Putin had told his military forces to be ready to go by Wednesday, but it is still unclear whether he has made a decision to attack his neighbor.

Read more here. 

-ABC News' Conor Finnegan

In another attempt to signal Western unity, U.S. Secretary of State Antony Blinken held a call with his British, French and German counterparts after speaking with Russian Foreign Minister Sergey Lavrov Tuesday morning, the U.S. Department of State confirmed.

The four foreign ministers discussed their coordinated "implementation of the massive consequences and severe costs to be imposed if Russia invades Ukraine," Blinken spokesperson Ned Price said in a statement.

In addition, Blinken's deputy, Wendy Sherman, spoke with her British, French, German and Italian counterparts Tuesday, the State Department said.

-ABC News' Conor Finnegan