Hill said Trump missed a warning that the nuclear option could be on the table in a conflict.
Hill told Politico that Putin made the warning in one of his final meetings with Trump.
"I don't think Trump figured out what he was saying," Hill, an expert on Russia, said.
A former US official said Russian President Vladimir Putin once warned then-President Donald Trump that if it came down to it, he would use the nuclear option but that Trump missed the warning.
Fiona Hill, the former senior director for Europe and Russia at the United States National Security Council, told Politico's Maura Reynolds that the road ahead in Russia's invasion of Ukraine is dangerous.
On Sunday, Putin ordered Russia's nuclear-deterrent forces to be put on high alert, meaning the weapons have been ordered to prepare for an increased possibility of launch, Insider's Connor Perrett reported.
Hill told Politico that the decision was Putin "making it very clear that nuclear is on the table."
Additionally, Hill said in one of the final meetings between Trump and Putin — where she was present — Putin tried to warn Trump about this very possibility but she didn't "think Trump figured out what he was saying."
She said: "Putin was making the point that: 'Well you know, Donald, we have these hypersonic missiles.' And Trump was saying, 'Well, we will get them too.' Putin was saying, 'Well, yes, you will get them eventually, but we've got them first.'"
Hill said there was "a menace in this exchange" and Putin was "putting us on notice that if push came to shove in some confrontational environment that the nuclear option would be on the table."
She told Politico that for Putin, having an "instrument" means wanting to use it.
"Why have it if you can't? He's already used a nuclear weapon in some respects," Hill said, referencing Russian operatives' use of radioactive polonium against the former spy and dissident Alexander Litvinenko in 2006 and the weapons-grade nerve agent, Novichok, against the agent Sergei Skripal and the opposition leader Alexei Navalny.
"So if anybody thinks that Putin wouldn't use something that he's got that is unusual and cruel, think again. Every time you think, 'No, he wouldn't, would he?' Well, yes, he would. And he wants us to know that, of course," Hill said.
Read the original article on Business Insider