March 13, 2022 Russia-Ukraine news

US national security adviser Jake Sullivan told CNN Sunday that while the Biden administration is “concerned about the possibility of escalation,” with respect to Russian President Vladimir Putin’s nuclear posture, “we have not seen anything that would require us to change our nuclear posture at this time.”

"We are watching this extremely closely, and obviously, the escalation risk with a nuclear power is severe, and it is a different kind of conflict than other conflicts the American people have seen over the years,” Sullivan told CNN’s Dana Bash on “State of the Union.” “And the American President, Joe Biden, has to take that responsibility extremely seriously, even as we redouble our efforts to support the Ukrainians. As things stand today, the United States has not adjusted our nuclear posture, but it is something that we monitor day by day, hour by hour, because it is a paramount priority to the President.”

He also said that Russian strikes on Lviv, approximately 12 miles from Ukraine’s border with Poland, is a sign Putin “is frustrated by the fact that his forces are not making the kind of progress that he thought that they would make against major cities, including Kyiv, that he is expanding the number of targets, that he is lashing out, and that he is trying to cause damage in every part of the country.”

A series of missile strikes early Sunday that struck the Yavoriv military training ground in the Lviv region of western Ukraine is the third strike by Russian forces in the western part of Ukraine “in the last couple of days,” Pentagon spokesman John Kirby said on ABC’s This Week Sunday.

There has been “some damage” to the military training facility, Kirby said, but the Pentagon is “still assessing and talking to the Ukrainians” about the extent of the damage from the strikes, Kirby said. 

No American service members were at the training facility; they had all left the training facility weeks prior, Kirby added.

When asked if a no-fly zone would have prevented this attack, Kirby said, “No, I don’t think so.” 

Kirby added that the US establishing a no-fly zone over Ukraine would mean war with Russia.

“The United States getting involved in combat in Ukraine right now, or over the skies of Ukraine right now leads to war with Russia, and there’s very little that you can see that would make sense for this war to be escalated between two nuclear powers,” Kirby said.

Leonid Slutsky, a Russian delegation member for the Ukraine-Russia talks, said “significant progress” has been made in negotiations with the Ukrainian delegation since the beginning of talks, Russian state news agency RIA reports.

“If we compare the positions of the Russia and Ukraine in the negotiations at the very beginning and now, we can see significant progress,” Slutsky said.

“I expect the progress may grow into a unified position of both delegations, and into a document for signing,” he said.

Background on talks: Talks between Ukraine's and Russia's diplomats last week yielded no discernible progress. Supposedly safe routes out of the country have repeatedly been contested. The civilian death toll continues to rise, and by the end of the week, both sides were trading accusations over the use of chemical weapons.

While Russian President Vladimir Putin said Friday there had been "certain positive advances" in negotiations with Ukraine, US and European officials and diplomats who spoke to CNN all expressed deep skepticism about the state of talks. None felt Putin's actions to date have suggested the Russian leader is ready to find a diplomatic off-ramp to end the war.

Kyiv region police said that an American journalist was killed by Russian forces in Irpin, Ukraine, according to social media posts on Sunday. Kyiv police said another American journalist was wounded by Russian troops. 

CNN has been unable to verify which media outlet the American journalists were working for in Ukraine. CNN has been unable to independently verify the death. 

A witness to the missile strike on the Yavoriv military base in western Ukraine, who was on the base when it happened, told CNN about his experience.

Up until Sunday morning, the Lviv region in western Ukraine was a safe haven in a war-torn country.

It was where families living further east sent their children to keep them safe.

Vasyl Kunets, a driver who lives in Novoyavorivsk, a town about 20 miles from Lviv, said that up until now, when the sirens indicating a potential air raid went off, he wasn’t too worried. He’d go to safety, but perhaps not as fast as he should have.

The war was still far away.

That all changed when Russian strikes hit the Yavoriv military training ground at the edge of Novoyavorivsk and killed 35 people, the Lviv regional administration said Sunday.

More than 30 missiles fired from warplanes over the Black and Azov seas had hit the military base, said Maksym Kozytsky, head of the Lviv regional military administration, in a statement posted to Facebook Sunday.

Suddenly, the war was on Kunets’ doorstep.

The training base is intertwined with the life in the town. Many of its residents are employed there, or in services supporting it. Those who don’t work for it directly know someone who does.

Kunets saw the damage they’ve inflicted first hand.

"I saw when the rocket hit the ground, I've seen the explosion and the smoke, a mushroom cloud of smoke and fire," he told CNN.

"It lasted 30 minutes and I heard maybe eight strikes, maybe some rockets crashing or part of rockets exploding separately, I don’t know."

Kunets told CNN the attack against the base "changed everything."

Kunets said he is now thinking about sending his two children away from Ukraine -- something he didn’t necessarily consider before.

"It feels less safe and more dangerous. Yesterday and the day before yesterday we were more relaxed and when we heard the alarms we didn't move so quick, we didn't take it too seriously. But today we are packing and being ready to leave very fast when we hear the alarm," he said.

CNN's Sofiya Harbuziuk contributed reporting to this post.

Pope Francis made an appeal for peace in Ukraine during his Angelus prayer in St. Peter’s Square on Sunday, calling Russia’s attacks an “unacceptable armed aggression” against Ukraine.

"In the name of God, let the cries of those who suffer be heard and let the bombings and attacks cease," he said.

The Pope asked the attacks to stop and added that the bombing of children’s hospitals and targeting civilians in Ukraine is “barbaric” and with “no valid strategic reason”.

“In the face of the barbarity of the killing of children, innocent people and defenseless civilians, there are no strategic reasons to be believed," the Pope said. "All that is needed is to stop the unacceptable armed aggression before it reduces cities to cemeteries."

Russian attacks continue Sunday morning with a spate of air strikes, with 35 people killed at a military training facility near the northwestern city of Lviv.

Russian offensive expands west: The Lviv region has largely been spared from Russia's bombardment since the invasion began, but it has come under increasing attacks in the last few days.

Dozens killed at military base: More than 30 missiles hit the Yavoriv military training ground early Sunday, killing 35 people and injuring 134 more. The site lies about 40 kilometers (25 miles) northwest of Lviv and less than 20 kilometers (12.5 miles) from the Polish border. It is home to the International Peacekeeping and Security Center (IPSC), which hosts training exercises with Western military personnel.

Russian air offensive hits heavily populated areas: While some Russian attacks were directed at critical infrastructure, other strikes appear to have hit heavily populated areas. The northern city of Chernihiv was struck for the third night in a row, and nine people were killed in a Russian bombardment near Mykolaiv, southern Ukraine.

Troops move closer to Kyiv: The bulk of Russian ground forces are now only 15.5 miles (25 kilometers) from the center of the Ukrainian capital, the UK's Ministry of Defence said Saturday.

Massive shelling in eastern Ukraine: On Sunday the head of the Luhansk regional administration, Serhiy Haidai, said there had been "massive shelling" of several towns, including Kreminna and Rubizhne, which had prevented buses from leaving with civilians. And an airstrike damaged Ukraine's historic Holy Dormition Sviatogirsk Lavra, an Orthodox monastery in Donetsk oblast, on Saturday evening.

President Volodymyr Zelensky has said the key task Sunday is to get the humanitarian convoy that is traveling towards the besieged city of Mariupol to its destination.

In a brief message on Instagram, Zelensky said, "Our humanitarian convoy is two hours away from Mariupol, just 80 kilometers away."

"We are doing everything to overcome the resistance of the occupiers, who are blocking even the Orthodox Church priests, who are escorting the convoy with food, water, medicines."

"Ukraine has supplied 100 tons, the basic needs for its citizens," he said.

The convoy set out Saturday from the city of Zaporizhzia. Mariupol has been under siege for more than a week. Much of the city is without power and water.

Zelensky claimed that after 18 days of conflict, "Russia has lost thousands of military vehicles, 74 aircraft and 86 helicopters."

CNN cannot independently verify claims of losses by either side in the conflict.