Ukraine says it killed a top Russian general; U.S. collects evidence of possible Russian war crimes

Rose Gottemoeller, a former deputy secretary general of NATO, said there are signs Russian President Vladimir Putin retains strong support in certain parts of the country.

"There are a number of very strong nationalists in Russia. Apparently they were present in … motorcades outside of the Kremlin yesterday, waving flags, supporting the president," she told CNBC's "Squawk Box Asia" on Tuesday.

Some polls also suggest that his popularity in Russia is still growing, she added.

On the other hand, people who are informed or have a stake in this, "like the oligarchs who have investments all over the world and want to keep their wealth" may be growing concerned as international sanctions hit.

"I am not surprised that they are becoming increasingly worried," Gottemoeller said.

"I don't think he's going to lose his grip on power, but perhaps some messages will start to get through to him," she said.

— Abigail Ng

Ukraine's defense intelligence agency said that Russian Army Major General Vitaly Gerasimov was killed, and other senior Russian Army officers "were also killed or wounded" in action near the city of Kharkiv.

Gerasimov was identified by the intelligence agency as the chief of staff and first deputy commander of the 41st Combined Arms Army.

The agency, which said Gerasimov had been "liquidated," claimed that data obtained related to his death near the city in northeast Ukraine "show significant problems with communication" in Russia's army, "and with the evacuation of their defeated units."

The post contains embedded audio files purporting to be intercepted communications between Russians discussing Gerasimov's death.

The reported killing comes days after another deputy commander of the 41st Combined, Gen. Andrei Sukhovetsky, was fatally shot by a Ukrainian sniper.

—Dan Mangan

Ukrainian President Volodymyr Zelenskyy released a new video Monday evening on Telegram, telling his fellow citizens that he is in central Kyiv at an official presidential residence, with no plans to leave the city despite the Russian assault.

"I am staying in Kyiv, on Bankova Street. Not hiding," Zelensky said, citing a street where both the Ukrainian president's office and the House of Chimeras official residence are located.

"I'm not afraid of anyone. For as long as it takes to win this war!" he added, according to an NBC News translation.

Zelenskyy's insistence upon staying in Kyiv as Russian missiles shell the capital and Russian troops advance on it has become a defining image of this conflict.

It has also helped inspire average Ukrainians to mount a fierce resistance to Russia's invasion, one that has surprised experts and military leaders around the world.

Speaking on Monday, Zelenskyy said Russian troops, "forgot that we are not afraid of police vans, of tanks, of machine guns when the most important thing is on our side - truth."

"You are not retreating. We are not retreating," he said.

--- Christina Wilkie

U.S. Ambassador to the United Nations Linda Thomas-Greenfield warned that the world should brace for the already-dire humanitarian crisis in Ukraine to worsen as Russia continues its invasion.

"The humanitarian toll of Putin's war on Ukraine is mounting," the ambassador said during a meeting of the UN Security Council, of which Russia is a member.

"Children are dying. People are fleeing their homes. And for what?" Thomas-Greenfield said after calling on Russia to commit to the establishment and protection of humanitarian corridors into and out of key areas of Ukraine.

"Young children have also been severely traumatized by the violence and destruction. They've witnessed so many things to the point that they've stopped speaking. The physical and psychological wounds of the is war will be long lasting," she said.

She said it was clear Putin plans to "destroy and terrorize Ukraine," even though many Russians don't want war and the Ukrainian people won't give up.

"Unfortunately, Mr. Putin doesn't seem to be listening, and we are concerned that the world needs to be prepared for a very long and very difficult road ahead," she said.

— Kevin Breuninger