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

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

Following President Joe Biden's remarks Tuesday, Senate leaders released a bipartisan statement of support for Ukraine that included a stark warning for Russia. 

In the event of an invasion in Ukraine, "Russia must be made to pay a severe price," said the statement, which was released by Senate Majority Leader Chuck Schumer and Senate Minority Leader Mitch McConnell, along with the leaders of several Senate committees.

Lawmakers would support "immediate imposition of strong, robust, and effective sanctions on Russia, as well as tough restrictions and controls on exports to Russia" in the event of an invasion, the statement said.

The senators noted that U.S. troops "stand ready" to enforce the security of Eastern allies and will "respond decisively to Russian efforts to undermine the security of the United States at home and abroad."

-ABC News' Allison Pecorin