I talked about all of this, Ukraine, as well as Vance's speech, with Europe's top diplomat, Kaja Kallas.

Kaja Kallas, thanks very much.

Welcome back to the "News Hour."

I appreciate it.

KAJA KALLAS, High Representative for Foreign Affairs and Security Policy, European Commission: Good to be here.

NICK SCHIFRIN: Last week, European officials came to Washington and were reassured, I'm told, by senior Trump administration officials about Ukraine.

Earlier this week, you and other senior European officials met with Vice President Vance in Paris and I'm told were reassured about the administration's focus on Ukraine.

But this week, we also heard from the defense secretary, Pete Hegseth, questioning whether Ukraine could ever get back occupied territory and essentially taking NATO off the table.

What's the impact of the mixed messages from the United States?

KAJA KALLAS: Well, the new administration is starting.

And, of course, we are building up a relationship with the new administration as well.

I mean, I have had good calls, a good call with Marco Rubio as well, who was also very assuring on Ukraine.

So, of course, we have to figure out the messages, what is right.

But this conference is a good place.

We have a lot of meetings with representatives to understand what are the ideas really of United States regarding Ukraine.

NICK SCHIFRIN: But can Europe actually make plans for Ukraine, can you and the United States work on a strategy for Ukraine when you getting these mixed messages?

KAJA KALLAS: Well, we have the strategy in place.

I mean, for us it's very clear.

It is to put the pressure on Russia to really stop this war.

When President Trump says that I just want the killing to stop, it's easy if Putin would stop bombing Ukraine.

This night, we heard that they were bombing the nuclear station.

So, clearly, Putin doesn't want peace.

So the pressure, the political, economical pressure should be on him, so that he realizes that he can't win and realizes it's a mistake to be there.

NICK SCHIFRIN: But President Trump also said this yesterday in the Oval Office -- quote -- "Yes, I do believe Putin wants peace" and -- quote -- "I trust him" on this subject.

What's your response to his statement?

KAJA KALLAS: Well, maybe he doesn't know Putin as well as we do.

So, well, Putin is not really keeping his promises, if you think about we have had such quick fixes, deals like Minsk II, Minsk II, and all... NICK SCHIFRIN: The previous acts of diplomacy between Russia and Ukraine that Europeans sponsored.

KAJA KALLAS: Yes, yes, previous cease-fire - - cease-fire agreements that were only necessary for Putin and Russia to get their act together more and attack in a bigger scale.

So I think the history proves that.

And that's why they only understand the language of strength.

And we have to be really strong and firm that you can't win here, because, if the United States is worried about China, if we can't get Russia right, we can't get China right either, because they are carefully watching how this goes.

NICK SCHIFRIN: One of the possibilities when it comes to a possible cease-fire in Ukraine, if we were to get to that, would be for European troops to deploy inside Ukraine.

In your conversations with European leaders, are they willing to consider that, even if, as Hegseth said this week, that the United States wouldn't protect them under Article V?

KAJA KALLAS: First, we have to understand that there's no peace.

In order to have peacekeeping troops, you need to have peace.

But, again, Putin doesn't want peace.

And that is a big problem that we need to address right now.

And, of course, if there is a peace, then we need to discuss, what are the security guarantees?

Yesterday, we heard the defense secretary of Ukraine saying that U.S. gave us promises in the Budapest Memorandum, give up your nuclear weapons and we will defend you when Russia attacks.

And where are you now?

So he was really very vocal in saying that you have not kept the promises you have gave - - you gave us.

So, right now, if we talk about security guarantees, then they really need to be credible.

What are the security guarantees that would really deter Russia from attacking again?

NICK SCHIFRIN: You and von der Leyen, the president of the European Commission, have both said publicly in the last couple of days that any kind of tariffs would essentially create conflict between the United States and Europe that is unnecessary.

Do you think the United States imposing tariffs on Europe would prevent Europe from working with the United States on Ukraine?

KAJA KALLAS: No, we have different cooperation points.

So it's clear that there are no winners in trade wars.

The consumers are the biggest losers, because the prices rise due to this.

So I hope that these things are settled between the United States and Europe, OK?

If there is trade imbalance, then, of course, we can see what we can do about this.

But starting a trade war, I don't think it's a good thing, because who is laughing on the side is China.

NICK SCHIFRIN: And, finally, we have been talking about this.

Most of the security conference is focused on this.

But the vice president, J.D.

Vance, gave a speech today in which he said that the greatest threat that faces -- that Europe faces is from within.

And he said -- quote -- "There is no security if you're afraid of the voices, the opinions, and the conscience that guide your own people.

If you're running in fear from your own voters, there's nothing America can do for you."

Is Europe afraid of the voices, opinions, and conscience of its own people?

KAJA KALLAS: Well, freedom of opinion, freedom of press is one of the fundamental values that the European Union stands for.

And, as you see, we have a lot of elections going on all the time, a lot of very different groups and very vocal.

And I don't really agree with that criticism.

And I think, of course, we deal with our domestic problems on our own, but we need to cooperate on the big international worries that we have.

And this is, for example, the war in Ukraine.

NICK SCHIFRIN: Kaja Kallas, thank you very much.

KAJA KALLAS: Thank you.