Polish, Baltic presidents meet Zelensky in Ukraine, pledge continued support and military aid

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The presidents of four countries on Russia's doorstep visited Ukraine on Wednesday and underscored their support for the embattled country, where they saw heavily damaged buildings and demanded accountability for what they called war crimes carried out by Russian forces.

The visit by the presidents of Poland, Lithuania, Latvia and Estonia was a strong show of solidarity by the leaders of the countries on NATO's eastern flank, three of them — like Ukraine — once part of the Soviet Union. They travelled by train to the Ukrainian capital, Kyiv, to meet Ukrainian leader Volodymyr Zelensky and visited Borodyanka, one of the towns near Kyiv where evidence of atrocities was found after Russian troops withdrew to focus on the country's east.

"The fight for Europe's future is happening here," Lithuanian President Gitanas Nauseda said, calling for tougher sanctions, including against Russia's oil and gas shipments and all the country's banks.

Elsewhere, in one of the most crucial battles of the war, Russia said more than 1,000 Ukrainian troops had surrendered in the besieged port of Mariupol, where Ukrainian forces have been holding out in pockets of the city. The information could not be verified.

Russia invaded on Feb. 24 with the goal, according to Western officials, of taking Kyiv, toppling the government and installing a Moscow-friendly regime. In the seven weeks since, the ground advance stalled and Russian forces lost potentially thousands of fighters — and the war has forced millions of Ukrainians to flee, rattled the world economy, threatened global food supplies and shattered Europe's post-Cold War balance.

A day after he called Russia's actions in Ukraine "a genocide," U.S. President Joe Biden approved $800 million US in new military assistance to Ukraine, saying weapons from the West have sustained Ukraine's fight so far and "we cannot rest now." The weapons include artillery systems, armoured personnel carriers and helicopters.

Appearing alongside Zelensky in an ornate room in Kyiv's historic Mariinskyi Palace on Tuesday, the European leaders — Nauseda, Estonian President Alar Karis, Poland's Andrzej Duda and Egils Levits of Latvia — reiterated their commitments to supporting Ukraine politically and with transfers of military aid.

"We know this history. We know what Russian occupation means. We know what Russian terrorism means," Duda said, adding that those who committed war crimes as well as those who gave the orders should be held accountable.

"If someone sends aircraft, if someone sends troops to shell residential districts, kill civilians, murder them, this is not war," he said. "This is cruelty, this is banditry, this is terrorism."

Zelensky said he's "sincerely thankful" to the U.S. for the new round of military assistance.

In his daily late-night address to the nation, Zelensky also said he was thankful for Wednesday's visit by the presidents of Poland, Estonia, Lithuania and Latvia.

He said those leaders "have helped us from the first day, those who did not hesitate to give us weapons, those who did not doubt whether to impose sanctions."

The Ukrainian president also said work was continuing to clear tens of thousands of unexploded shells, mines and trip wires that were left behind in northern Ukraine by the retreating Russians.