WASHINGTON - The United States and NATO on Sunday condemned Russian President Vladimir Putin's order to put his nuclear forces on high alert as dangerous and unacceptable, while the White House said it was considering imposing new sanctions on Russia's energy sector.
In issuing the order to prepare Russia's nuclear weapons for increased readiness for launch, Putin cited "aggressive statements" from NATO allies and widespread sanctions imposed by Western nations that have already disrupted his country's economy.
The U.S. ambassador to the United Nations, Linda Thomas-Greenfield, said on CBS's "Face the Nation" program that Putin's actions had escalated the conflict and were "unacceptable."
Thomas-Greenfield said the United States welcomed the news that Russian and Ukrainian officials would meet for talks on the border Belarus, but that it "remains to be seen" if Russia is acting in good faith.
Asked if there was a threat of chemical and biological weapons being used by Russia, Thomas-Greenfield said of Putin, "Certainly nothing is off the table with this guy. He's willing to use whatever tools he can to intimidate Ukrainians and the world."
"This is dangerous rhetoric. This is a behavior which is irresponsible," NATO Secretary-General Jens Stoltenberg said on CNN's "State of the Union" program, referring to Russia's nuclear alert status.
White House Press Secretary Jen Psaki said Putin was responding to an imaginary threat.
"We've seen him do this time and time again. At no point has Russia been under threat from NATO, has Russia been under threat from Ukraine," Psaki said on ABC's "This Week" program.
"This is all a pattern from President Putin and we're going to stand up to it. We have the ability to defend ourselves, but we also need to call out what we're seeing here from President Putin," Psaki added.
Ukraine said Putin's order regarding Russian nuclear forces was calculated to put pressure at the start of talks but that Kyiv would not be cowed.
The United States also has not taken sanctions targeting Russia's energy sector off the table, Psaki said.
"We want to take every step to maximize the impact of consequences on President Putin while minimizing the impact on the American people and the global community. And so energy sanctions are certainly on the table. We have not taken those off. But we also want to do that and make sure we're minimizing the impact on the global marketplace and do it in a united way," Psaki said.
The United States is open to providing additional assistance to Ukraine, Psaki said.
U.S. Secretary of State Antony Blinken on Sunday announced $54 million in new humanitarian aid for Ukrainians affected by the invasion, which was in addition to the $350 million sent by the United States last week.
"This includes the provision of food, safe drinking water, shelter, emergency health care, winterization, and protection," Blinken said in a statement.
(Reporting by Doina Chiacu and James Oliphant; Additional reporting by Steve Holland and Joel Schectman; Editing by Ross Colvin and Will Dunham)