(CNN) President Joe Biden's stark warning Thursday night that the world faces the highest prospect of nuclear war in 60 years was not based on any new intelligence about Russian President Vladimir Putin's intentions or changes in Russia's nuclear posture, multiple US officials told CNN.
The US still has seen no evidence that Putin is moving toward using Russia's nuclear capability, nor is there any intelligence showing he's decided to do so. But Biden's comments -- laid out in starker terms than other US officials have used to date -- reflected heightened concerns inside his administration about the risk of Russia carrying out a nuclear strike in Ukraine, where Russian forces have recently faced a string of defeats.
Biden's blunt assessment caught several senior US officials by surprise, largely due to that lack of any new intelligence to drive them and the grim language Biden deployed.
One senior administration official said Biden was speaking "frankly" in his remarks at a Democratic fundraiser in New York, reflecting heightened concern based on Putin's recent nuclear threats.
The threat has long been high on the minds of the administration's national security officials, and the battlefield failures have only served to elevate regular discussions and contingency planning about the issue. But there was no moment, briefing or new information that Biden was privy to that signaled any actual shift in Russian posture.
And the morning after Biden's comments, administration officials said the US's nuclear stance has not changed.
"Our posture hasn't changed," one official said of the US preparations. "If there was some new piece of alarming information, it obviously would."
There simply isn't much -- if any -- precedent in the last six decades of a president so bluntly warning of looming catastrophe. The divergence in tone between Biden and his top national security officials is striking, with the President moving sharply away from the coordinated effort to calmly warn against saber rattling, but not rhetorically escalate anything.
Yet Biden's remarks, as one official noted, do reflect reality -- a reality that may be difficult to grasp due to the combination of a far-off war and a post-Cold War era when nuclear threats have simply disappeared from daily risks. Those risks have grown acutely in the last eight months, even if there is no tangible evidence Putin has made concrete moves in that direction.
Putin's nuclear saber-rattling led US national security adviser Jake Sullivan to warn of "catastrophic consequences" late last month should Moscow move to use nuclear weapons -- and Putin has only further ratcheted up his rhetoric since.
Biden's remarks serve as a window into a very real, very ongoing discussion inside his administration as the seek to calibrate the response to that environment.
CNN reported last week that the US is considering how to respond to a range of potential scenarios, including fears that Russians could use tactical nuclear weapons, according to three sources briefed on the latest intelligence. The US has since the start of the conflict been developing contingency plans to respond, including to the possibility that Putin could escalate via a step just short of a nuclear attack on Ukraine, through what one source described as a "nuclear display," such as a potential military strike on the Zaporizhzhia nuclear power plant, or the detonation of a nuclear device at high-altitude or away from populated areas.
The threat of Putin using nuclear weapons is certainly "elevated" compared to earlier in the year, multiple sources told CNN late last month. But multiple officials familiar with the latest intelligence said that the likelihood Putin will use a tactical nuclear weapon in Ukraine is still not probable. The intelligence community is closely watching for any signs that the Russian leader's calculus has changed.
The comments were also the latest unguarded moment from Biden during an off-camera fundraiser, where the President has repeatedly deployed more candor and colorful rhetoric he might in scripted remarks. Officials say his off-the-cuff remarks at fundraisers tend to be a brief and unvarnished window into real concerns or debates Biden is grappling with at the moment.
Typically held with only a few dozen donors, Biden's fundraisers are more intimate occasions where he often speaks from handwritten notes, only loosely following a script he's written for himself. Like at his public events, Biden speaks from a handheld microphone during his fundraisers and usually roams around the room while he's talking. Reporters are allowed to listen and report on the President's remarks but not film them, a convention that began during the Obama presidency.
His remarks are usually only slotted for 10 minutes but in the past he has stretched to half an hour or more, expounding on various topics. After the remarks, reporters are ushered out while Biden takes a few questions from the donors.
While most of what Biden says at the fundraisers is familiar, he has made comments previously that went beyond his remarks to larger audiences. It was a fundraiser in Maryland where Biden declared Trump-aligned Republicans "semi-fascist" and where he said the views of the Catholic Church on abortion had changed.
Biden's comments about the prospect of nuclear Armageddon were not scripted and aides back in Washington first learned about his remarks through news reports and dispatches from the press pool in the room.
Biden's reference to the Cuban Missile Crisis was notable, both because it was the last time a US president spoke so overtly about the risks of a potentially impending catastrophe, but also because it's 60th anniversary is just a few days away.
Implicit in Biden's comments, however, was the risks posed by a critical difference. President John F. Kennedy and his team weighed a series of potential off-ramps and backchannel proposals that could head off the crisis. The Soviet leader at the time -- Nikita Khrushchev, who had seen the horrors of World War II -- always made clear he understood the stakes of a nuclear standoff, even if his strategic calculation in Cuba was woefully off-base. Mutually assured destruction was the baseline, and even at their worst moments and most bellicose threats, the dealings between Kennedy and Khrushchev reflected that reality.
In contrast, Biden's comments about an inability to identify an off-ramp -- particularly as Putin's military flails -- raises a very real concern that the long-standing mutual understanding may not be as assured as assumed. Putin's at-times rambling and bellicose speech last Friday only served to exacerbate that concern inside the White House, one official said.
Biden's use of the word "Armageddon" has drawn all the headlines, but the context of that remark is critically important. White House officials have stressed that the idea Russia could deploy "tactical" strikes, as per their doctrine, does not represent some kind of half measure or step below maximum escalation.
The President's use of Armageddon served to illustrate that point -- there's no escalation ladder when it comes to nuclear weapons, tactical or otherwise. Any move in that direction sets off a cascading response that only has one outcome.
Several officials pointed out that Putin's nuclear saber rattling isn't new, and US officials have been grappling with the threats and the potential for their use since the first days of the war.
But White House officials closely watched -- and studied for clues -- Putin's speech last week -- and much like his speech just prior to the invasion, it raised alarms. It's been an element of several internal discussions in recent days, highlighting that while the world may brush off the latest in months of Putin statements seemingly detached from obvious reality, the Biden "doesn't have that luxury," one official said.
One official characterized the speech as "insane," and while that bolstered the US view of Russian weakness and isolation, it also further increased concern about Putin's willingness to escalate beyond the level of a rational actor.
That's important context when thinking about Biden's remarks, one official noted.
White House officials decided not to say anything publicly Thursday night, and there are no plans to address the remarks in isolation so far on Friday morning. If Biden wants to address it himself, it will be apparent when he departs for his Maryland event later in the morning, one official said.
More broadly, the most important element remains that US officials have seen no change in posture or specific intelligence that raises the threat level above where it has been.
There have been direct communications to Moscow in the last several weeks detailing the scale of the US response should Putin decide to go down that path. Those details remain closely held, and officials say that won't change any time soon.