During an on-camera briefing at the Pentagon on Wednesday, Pentagon press secretary John Kirby stated that “additional Russian military forces are moving into” Ukraine‘s Donetsk and Luhansk areas.

Russia‘s military buildup along Ukraine’s border is now “at a state of readiness where they could attack at any time,” according to Ukrainian officials, Kirby said.

Also read: Ukraine President faces silence upon calling Vladimir Putin, addresses Russian citizens

Kirby emphasised that if Russian President Vladimir Putin decides to invade Ukraine in its entirety, it will be a “war of choice” that “it won’t be bloodless.”

“There will be suffering,” Kirby added. “There will be sacrifice. And all of that must and should be laid at his feet. Because he’s doing this by choice.”

Russia has continued to show no signs of wanting to de-escalate the confrontation, according to Kirby, and the Pentagon has seen “quite the opposite.”

Also read: ‘We are different… not a reason to be enemies,’ Ukraine President addresses Russian citizens

Kirby also stated that the Pentagon could not confirm the amount of Russian troops who had moved into these two zones, “what the formations are, what the capabilities are,” but that the Pentagon believes Russian troops are on their way.

“We can’t confirm with any great specificity the numbers, and what the formations are, what the capabilities are, but we certainly believe that that’s happening,” Kirby said.

“We’ve seen sadly and unfortunately no indication that he’s willing to de-escalate, move those troops back home, and actually get to some sort of serious diplomatic solution, every indication rather that we see is quite the opposite,” he added.

Also read: Ukraine government and commercial websites faces data-wiping hack, says researchers

Kirby said if Putin chooses war, he’ll be doing so with “diplomacy and options still left on the table.”

Russian President Vladimir Putin on Monday declared Ukraine’s separatist areas of Donetsk and Luhansk to be independent states.

The move drew considerable outrage from NATO allies and the United States.