MICHEL MARTIN, HOST:

The humanitarian crisis in Ukraine is growing as Russia continues its invasion of the country. Today, the United Nations said nearly a quarter of Ukraine's population has been displaced by the war. In the major southern city of Mariupol, tens of thousands of people remain trapped as Russian troops move closer to the city center. And today, Russia claimed it used a hypersonic missile, which, if confirmed, would be the first known use of this weapon during the war. It was used to strike a munitions warehouse in western Ukraine. To get a clearer picture of the current state of the fighting and Ukraine's military strategy, we called an adviser to Ukraine's defense minister, Markiyan Lubkivsky. Mr. Lubkivsky, welcome. Thank you for joining us.

MARKIYAN LUBKIVSKY: Thank you for having me here.

MARTIN: And I'm going to assume that you're only going to tell me what it is safe for you to tell me. We're not going to disclose your location, for example. So with that understanding, Russian forces have been stalled for days now, about 10 miles outside of the capital city, Kyiv. This has been seen as helpful to Ukraine's defense, but now the fear is that Russia is going to ramp up its artillery strikes on the city and basically mount a siege. Is there anything you can tell us about the strategy for dealing with that and defending the city?

LUBKIVSKY: So thank you so much. We are ready for defense, and we will defend our city, our capital. President of Ukraine is staying in the city. Every citizen of Kyiv is ready to protect his home, his street, his family. Yeah, you're absolutely right saying that the aggressor is very close to our capital, but we are prepared for that. We have very good and very prepared, well-prepared army. Army will protect Kyiv from any kind of attack. Yeah, the strategy of Putin was to take Kyiv in two, three days, but he never realized that.

MARTIN: The U.S. has said it is rushing additional small-arms anti-tank and anti-aircraft weapons to Ukraine. Is there anything you can tell us about whether you have received those? Are you getting what you asked for, and has it been helpful?

LUBKIVSKY: It is very helpful. We are very grateful to the U.S. government, to U.S. president, to all people in the United States of America. Unfortunately, our main request was to close the sky over Ukraine, and we did not get that. But from the other side, we were equipped with ammunition, with the weapons. And now our army is using them very efficiently.

MARTIN: So as you pointed out, the U.S. and other NATO countries have refused, declined to agree to the request to establish a no-fly zone. We've discussed many times their reasoning for that. But Ukraine, as we understand it, has been in discussions over a particular anti-aircraft system called the S-300. It's a mobile air defense system that can target aircraft more than 30,000 feet in the air. What would that weapon do for your fight? And does it look like you'll get it?

LUBKIVSKY: Yeah. Again, I will be very poor with the details, but yes, we are working with these Soviet weapons quite efficiently. And again, so I will use the - I will quote Winston Churchill, who said, "give us the tools, and we will finish the job." So this is the main thing. And this is our message. This is our message to the Western and NATO countries.

MARTIN: It has been reported that of the 20 Russian generals in Ukraine, at least four have been killed. What is the significance of that? Why do you feel that that is important?

LUBKIVSKY: You know, we don't - you know, due to Russian propaganda, Russian media are saying that their army is No. 2 in the world, and this is not the truth. So it's important for us. We are not attacking anybody. We are protecting our land. We are defending ourselves. And this is the signal to the rest of Russian army. Don't come here.

MARTIN: Do you have any sense - we understand that there has been just a very aggressive crackdown on information flow into Russia. And I don't know if you would have any sense of this, but do you have any sense that the Russian public is aware of these Russian casualties?

LUBKIVSKY: I'm not sure because Russian society is quite closed. They don't have enough information from the ground. We are trying to speak to them, to provide them with the facts. I will describe your question with one fact. You know that negotiations are ongoing and when our colleagues, our Ukrainian diplomats met Russians in Belorussia, so they were approached by Belarussian diplomats, Belarussian hosts, and they - and the question was, why did you attack Belorussia? So they think that we attacked - that we are aggressors and we attacked Belorussia and Russia. So this is, you know, this is unbelievable. So they are in some kind of closed society without information. And the most important thing is to speak to the mothers, to two sisters of killed soldiers, to, you know, to send them a message. The only thing if you are coming here with a weapon, with aggression, you will find death here.

MARTIN: Before we let you go, how are you, and how are your spirits? How are those of the other leaders of the government right now? As you've indicated, they're all staying. How are...

LUBKIVSKY: They are OK.

MARTIN: Yeah. How are you doing?

LUBKIVSKY: The spirit of Ukrainian army is very, very, very high. The morale is very high. Our army is supported by civilians, by the Ukrainians. I never expected that Ukrainians would be so united, and I think - I think - that that was the crucial mistake made by Putin. He never expected that his army would not leave here with the flowers. So then this is our message. We are peaceful nation. We are ready for negotiations. But please stop your army. Provide people with a humanitarian corridor to take other people from the areas which are under attack of missiles. But we will protect our land, and we will win.

MARTIN: That was Markiyan Lubkivsky. He is an adviser to the Ukrainian defense minister. We're not disclosing his location for safety reasons, but he's in Ukraine. Markiyan Lubkivsky, thank you so much for speaking with us.

LUBKIVSKY: Thank you so much. Thank you for having me with you. Transcript provided by NPR, Copyright NPR.