Tonight on PBS News Weekend, Russia launches a barrage of drones into Ukraine just hours after President Trump raises doubts about Putin's commitment to peace.

Then as President Trump's second term approaches day 100, we examine the most controversial and consequential

moments and how global warming may be endangering a treasure trove of cultural artifacts

in remote Alaska.

The objects we're finding are important not just to local folks in their heritage, but to our collective heritage as humans.

Good evening. I'm John Yang. Russia continues its deadly assaults on Ukraine, overnight launching a sweeping drone attack that killed at least four people.

It comes a day after President Trump met with Ukrainian President Volodemar Zelensky at the Vatican before Pope Francis's funeral.

Both described the discussion in positive terms. After that meeting,

Mr. Trump took to social media to criticize Russian leader Vladimir Putin. There was no reason

for Putin to be shooting missiles into civilian areas, cities, and towns. It makes me think that

maybe he doesn't want to stop the war. He's just tapping me along.

William Taylor is a distinguished fellow at the Atlantic Council's Eurasia Center.

He was U.S. ambassador to Ukraine under George W. Bush and the temporary head of mission there in the first Trump administration, later testifying in Mr. Trump's impeachment.

Mr. Taylor, what do you make of that social media post saying that maybe Putin is just tapping

him along?

So, John, I think the president is realizing after that evidence of these attacks and other

attacks on religious holidays, we know two weeks ago, three weeks ago now.

And we know actually the discussion that President

Trump had with President Zelensky, for the first time a direct, unfiltered conversation

between the two presidents, that President Trump is realizing that President Putin may not be

serious about this negotiation, about stopping this war. I believe that Putin is not

serious about stopping this war, but I think the president may be coming to that same conclusion.

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