Tonight on PBS News Weekend, the Trump administration lays out its vision for the U.S.

role in the world, taking America first policies global.

Then we explore how artificial intelligence is helping predict preterm births.

And the benefits and risks of an icy plunge as

wintertime outdoor swimming gains a global following.

It's really refreshing.

I think it's in terms that every single person has to have once in their lifetimes.

Here in winter.

Yes, in winter.

And I love it.

It's really cold, but we love it.

Good evening. I'm John Yang. White House envoys met again with Ukrainian officials in Miami today to discuss President Trump's proposed path to peace in Ukraine.

It was their seventh meeting over two weeks, including a session this past Sunday that included Secretary of State Marco Rubio.

The State Department said they've agreed on a key item,

a peacekeeping arrangement for post-war Ukraine.

The administration's national security strategy released this week

says ending the war is a core U.S. interest

in order to stabilize European economies,

prevent unintended escalation or expansion of the war, and reestablish strategic stability with Russia.

The congressionally mandated document reflects a shift from the stance of previous administrations, including Mr. Trump's first term.

Earlier, I spoke with Matthew Kronig, Vice President and Senior Director of the Atlantic Council's Skokroft Center for Strategy and Security.

He helped write similar strategy statements under President's George W. Bush and Obama and in the first Trump term.

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