• President Joe Biden convened a meeting of the National Security Council Sunday amid the rapidly deteriorating security conditions in Ukraine.
• In a Friday address, Biden said the United States believes that Russian President Vladimir Putin has decided to carry out an attack on Ukraine "in the coming days."
• The Biden administration has previously declined to predict Putin's playbook even as Russia has deployed nearly half of its military to Ukraine's northern and eastern flank.

WASHINGTON –President Joe Biden convened a meeting of the National Security Council Sunday amid the rapidly deteriorating security conditions in Ukraine.

In a statement Saturday evening, White House press secretary Jen Psaki said the president was receiving regular updates over the weekend about events on the ground.

News about Biden's interaction with members of his national security team took on a new sense of urgency this weekend after the president said he believed Russian President Vladimir Putin had decided to carry out an attack on Ukraine "in the coming days."

"We have reason to believe the Russian forces are planning and intend to attack Ukraine in the coming week, in the coming days," Biden said Friday in a formal address to the nation, his second in the past week. "We believe that they will target Ukraine's capital, Kyiv, a city of 2.8 million innocent people."

Revealing information like this about an adversary's battle plans is highly unusual, and Biden's prediction sent shockwaves around the world. Russia currently has 190,000 troops deployed on Ukraine's northern and eastern border — nearly half of the nation's military.

Yet even as both Russian troop movements and U.S. intelligence about Putin's plan suggest war is imminent, Russia's top diplomat in Washington still insisted on Sunday that his country posed no danger to Ukraine.

"We have a legitimate right to have our troops where we want on Russian territory ... and we are not a threat to anybody," said Anatoly Antonov, Russia's ambassador to the United States, on CBS's "Face the Nation."

Antonov said point-blank that Russia's looming invasion isn't really about Ukraine. Rather, it is part of a broader effort by Moscow to try and force NATO members to sign a legally binding pledge not to expand the defense alliance further East. NATO members have long called this demand a non-starter.

Even with diplomatic efforts at an apparent stalemate and citizens of Kyiv taking up arms, Secretary of State Antony Blinken said he believes there is still time for Putin to choose diplomacy.

"Until the tanks are rolling and the planes are in the air we are going to try everything we possibly can to get President Putin to reverse the decision we believe he's made," Blinken said on NBC's "Meet the Press."

"Until the last minute, there is still an option for him to pull back," he added.

Blinken is scheduled to meet with his Russian counterpart, Foreign Minister Sergey Lavrov, in the latter part of this week.

While still pressing for diplomatic talks, U.S. officials have also begun a concerted effort to communicate to the public what the human costs of an invasion will be if Putin goes ahead with plans to attack.

"Russian missiles and bombs will drop across Ukraine. Communications will be jammed, cyberattacks will shut down key Ukrainian institutions. After that, Russian tanks and soldiers will advance on key targets that have already been identified and mapped out in detailed plans," Blinken recently told members of the U.N. Security Council.

Chairman of the Joint Chiefs of Staff and U.S. Army Gen. Mark Milley painted an equally grim picture of what could lie ahead for Ukraine, telling Pentagon reporters that Russia's troop buildup was unlike anything he has seen during his four-decade military career.

He said the Russians have deployed air forces, naval forces, special forces, cyber electronic warfare, command and control, logistics engineers and other capabilities along Ukraine's border.

"Given the type of forces that are arrayed, the ground maneuver forces, the artillery, the ballistic missiles, the air forces, all of it packaged together. If that was unleashed on Ukraine, it would be significant, very significant, and it would result in a significant amount of casualties," Milley said on Jan. 28.

"It would be horrific," he added.