Russia-Ukraine updates: US sanctions Russian military shipbuilder, diamond miner

President Joe Biden told the Ukrainian people, "We stand with you" in an address he gave at the Royal Castle in Warsaw, Poland, Saturday.

"We’ll not cease the efforts to get humanitarian relief wherever it is needed in Ukraine and for the people who’ve made it out of Ukraine. Notwithstanding the brutality of Vladimir Putin, let there be no doubt that this war [has] already been a strategic failure for Russia," Biden said.

"Putin thought Ukrainians would roll over and not fight, not much of a student of history," Biden said.

Biden also addressed the Russian people, telling them: "You, the Russian people, are not our enemy."

"The American people stand with you and the brave people of Ukraine for peace," Biden said.

In an address from Warsaw Saturday, President Joe Biden made remarks seemingly directed at Russian President Vladimir Putin and his invasion of Ukraine. "For god's sake, this man cannot remain in power," Biden said.

After the speech, the White House released a statement saying the president wasn't calling for a regime change.

“The President’s point was that Putin cannot be allowed to exercise power over his neighbors or the region. He was not discussing Putin’s power in Russia, or regime change,” a White House official said.

"These are not the actions of a great nation," Biden said, addressing the Russian people during his speech.

"Vladimir Putin's aggression have cut you, the Russian people, off from the rest of the world, and it’s taking Russia back to the 19th century. This is not who you are," Biden said.

Biden praised Ukrainian resistance, saying the U.S. stands with the people of Ukraine and will continue to support them.

"A dictator bent on rebuilding an empire will never erase a people's love for liberty. Brutality will never grind down their will to be free. Ukraine will never be a victory for Russia, for free people refuse to live in a world of hopelessness and darkness," Biden said.

President Joe Biden warned: "Don't even think about moving onto one single inch of NATO territory," Saturday in an address that just ended.

Biden spoke to an audience of between 750 and 1,000 attendees in Warsaw, Poland, including Polish President Andrzej Duda, members of parliament, local officials, students from local universities and U.S. embassy staff, according to the White House.

This is a developing story. Check the blog for updates.

"Continuous battles" for Mariupol's territory continue daily, the city's deputy mayor, Serhiy Orlov, told ABC News Saturday.

The deputy mayor estimated that 150,000 people remain in the city.

He was unable to give an update on the hundreds of of civilians believed to have been killed in Russian strikes that hit a theater that was being used as a shelter. A sign indicated that children were sheltering inside satellite imagery shows.

"The situation becomes worse, so people still have a lack of everything," he told ABC News in a remote interview.

The mayor added: "The lack of water, electricity, heat and sanitary system, lack of medicine, food. So they're just surviving … it's not a secret that from 50 to 100 airstrikes, the Russian aircraft do each day and the one-third or one-half of all the bombing of airstrikes in Ukraine goes on Mariupol."

-ABC News' Guy Davies