Kyiv Mayor Vitali Klitschko said during an interview with German newspaper BILD that Russian President Vladimir Putin was guilty of "genocide" after Ukrainian forces retook previously occupied parts of the city, discovering numerous bodies and booby-traps.

"What happened in Bucha and other suburbs of Kyiv can only be described as genocide. These are cruel war games that Putin is responsible for there. Civilians shot with their hands bandaged," he said, according to the report.

The bodies of 410 civilians were removed from the streets in and around Kyiv as Ukrainian forces repelled Russian troops from the area.

Russia’s Defense Ministry has disputed these facts and the claims of committing genocide.

The Associated Press contributed to this report.

Siuzanna Iglidan, a Ukrainian musician and opera singer, performed at the Grammys alongside award-winning American artist John Legend.

The duo, who sang "Free," were joined by Ukrainians singer-actress Mika Newton and poet Lyuba Yakimchuk.

The performance followed a video address by Ukrainian president Volodymyr Zelenskyy, where he encouraged people to sing and play music to "fill the silence" caused by his country's war with Russia.

“Our musicians wear body armor instead of tuxedos,” Zelenskyy said. “We are fighting Russia, which brings horrible silence with its bombs. The dead silence. Fill the silence with your music.”

"Tell the truth about the war on your social networks, on TV. Support us in any way you can any, but not silence. And then peace will come to all our cities,” the Ukrainian president added.

Ahead of her performance, Iglidan said she was "honored" to represent her country.

The Associated Press contributed to this report.

Ukrainian President Volodymyr Zelenskyy addressed the 64th annual Grammy Awards on Sunday in a pre-taped speech that emphasized the suffering on his country.

"The war. What is more opposite of music? The silence of ruined cities and killed people,” said Zelenskyy. “Our children draw swooping rockets, not shooting stars. Over 400 children have been injured and 153 children died, and we will never see them drawing. Our parents are happy to wake up in the morning in bomb shelters, but alive. Our loved ones don’t know if we will be together again. The war doesn’t let us choose who survives and who stays in eternal silence."

“Our musicians wear body armor instead of tuxedos," he continued. "They sing to the wounded in hospitals. Even to those who can’t hear them. But the music will break through anyway. We defend our freedom. To live. To love. To sound. On our land, we are fighting Russia which brings horrible silence with its bombs. Fill the silence with your music. Fill it today. Tell our story. Tell the truth about the war on your social networks and TV. But not silence."

After Russian forces scaled back operations in the outskirts of Ukraine’s capital, evidence emerged of brutal war crimes against civilians.

Human Rights Watch has documented evidence of summary executions, unlawful violence and threats against civilians, and repeated rape between February 27 and March 14. A report from the organization also implicates Russian soldiers in looting civilian property, including food, clothing, and firewood. 

Read more: Russian-controlled areas near Ukraine’s capital show evidence of war crimes: Human Rights Watch

Bodies wrapped in black tarp lie in a mass grave on the outskirts of Kyiv as Ukrainian troops assess the destruction after Russian troops withdrew from the area, according to photos from The Associated Press.

In another village, the bodies of a mayor, her husband and son, and of a man believed to be a Ukrainian serviceman, also lie in a muddy pit behind a plot of land with houses where Russian forces had slept.

A lifeless body of a man with his hands tied behind his back is discovered on the ground in Bucha, northwest of Kyiv. Ukrainian authorities accuse Russian forces of committing war crimes and leaving behind a "scene from a horror movie." 

Zelenskyy said hundreds of people have been killed in Bucha and other cities, including civilians who were shot by Russian forces.The Russian defense ministry has denied any “crimes” in the city of Bucha, which in the past few days quickly transformed into the epicenter of calls for human rights investigations.

The Associated Press contributed to this report.

Read more: Ukraine war photos: Horrific findings after Russian retreat from Kyiv outskirts

Ukrainian President Volodymyr Zelenskyy said Sunday that Western nations would impose more sanctions on Russia after the alleged killing of civilians in Bucha and other Ukrainian cities, but emphasized that such a move might not be an adequate punishment.

“There will definitely be a new sanctions package against Russia," Zelenskyy said during a press conference. "But I'm sure that's not enough. We need more conclusions. Not only about Russia, but also about the political behavior that actually allowed this evil to come to our land."

Zelenskyy said hundreds of people have been killed in Bucha and other cities, including civilians who were shot by Russian forces.

The Russian defense ministry has denied any “crimes” in the city of Bucha, which in the past few days quickly transformed into the epicenter of calls for human rights investigations.The ministry insisted that any evidence of atrocities have been “staged” for the media.

Ukrainian President Volodymyr Zelenskyy on Sunday reacted to disturbing new images coming out of a suburb of the capital Kyiv showing the bodies of executed civilians by calling Russia's attacks "genocide."

"Indeed, this is genocide," Zelenskyy said during a "Face the Nation" interview on CBS. "The elimination of a whole nation, and the people -- we are citizens of Ukraine."

"We have more than a hundred nationalities. This is about destruction and extermination of all these nationalities," Zelenskyy told host Margaret Brennan.

"We are the citizens of Ukraine and we don’t want to be subdued to the policy of Russian Federation. This is the reason we are being destroyed and exterminated. And this is happening in the Europe of the 21st century. So this is the torture of the whole nation."

Read more: Zelenskyy reacts to devastating images coming out of Ukraine: 'This is genocide'

Russian forces destroyed an oil refinery and hit other “critical infrastructure” near the port city of Odesa.

Dmytro Lunin, governor for the region, said that the refinery had been destroyed in a rocket attack.

"The fire at the refinery has been extinguished but the facility has been completely destroyed and can no longer function," he said.

Several rockets also hit Mykolaiv, an interior ministry aide said.

Secretary of State Antony Blinken said the U.S. cannot become "numb" to images of death and destruction in Ukraine, vowing "accountability" for war crimes. 

"You can't help but see these images as a punch to the gut," Blinken said on CNN’s State of the Union on Sunday. He was reacting to photos out of Bucha, Ukraine, near Kyiv, showing photos of civilian men who were reportedly executed and left on the streets, according to the city’s mayor. 

Blinken said the U.S. is documenting any potential war crimes and vowed "accountability." 

Click here to read more.

The Russian defense ministry has issued a denial of any “crimes” in the city of Bucha, which in the past few days quickly transformed into the epicenter of calls for human rights investigations.

The ministry insisted that any evidence of atrocities have been “staged” for the media.

“All photographs and video materials published by the Kyiv regime, allegedly testifying to some kind of "crimes" by Russian military personnel in the city of Bucha, are another provocation,” the ministry said in a statement.

The ministry stressed that all Russian troops had left the city on Mar. 30 and that the mayor of Bucha “did not even mention” any of the crimes that have surfaced in the days since then.

German Chancellor Olaf Scholz has demanded that international organizations be given access to areas with reported mass graves so they can investigate possible crimes by the Russian military.

Scholz also denounced the “terrible and horrific images” from out of Bucha, where Russian troops reportedly left civilians dead in the streets.

“We must relentlessly investigate the crimes of the Russian military and hold the perpetrators accountable,” Scholz tweeted.

The Russian retreat from the Ukrainian town of Bucha has revealed the devastation troops visited upon the civilians during their occupation.

A Reuters reporter walked the streets with a policeman who claimed the troops killed more than 300 civilians and left them “scattered” about the town. The reporter wrote that some of the dead still held grocery bags, and it appeared they had died many days if not weeks earlier.

Mayor Anatoliy Fedoruk said the town opened a mass grave at one church ground.

Ukrainian troops moved cautiously to retake territory north of the country's capital on Saturday, using cables to pull the bodies of civilians off the streets in one town out of fear that Russian forces might have booby-trapped them before leaving.

Ukrainian President Volodymyr Zelenskyy warned in his nightly video address hours earlier that departing Russian troops were creating a "catastrophic" situation for civilians by leaving mines around homes, abandoned equipment and "even the bodies of those killed."

His claims could not be independently verified.

Click here to read more.

David Arakhamia, Ukraine's chief negotiator amid ongoing peace talks with Russia, claims Moscow has "verbally" agreed to Kyiv’s negotiations, according to a report.

"The Russian Federation has given an official answer to all positions, which is that they accept the (Ukrainian) position, except for the issue of Crimea (annexed by Russia in 2014)," Arakhamia said, AFP News Agency reported.

The negotiator clarified that the agreement is not "official confirmation in writing," but that an agreement could be nearing, according to the report.  

Arakhamia noted stipulations Moscow agreed to included the neutrality of Ukraine "will be the only way out of this situation," AFP News Agency reported.

Ret. Brig. Gen. Anthony Tata calls Russia's recent movements 'repositioning of forces.'

Ukraine presidential advisor Oleksiy Arestovych said during a briefing on Sunday that the next "week or two" could determine the outcome of the Russia-Ukraine War, according to a report.

After Russia's military troops invaded Ukraine nearly 40 days ago, the larger army's might has been repeatedly stalled by Ukraine's military determination and will to save their homeland, resulting in a slowed attack and severe losses for Russia.

Russia's lack of swift victory has brought both countries to the negotiation table, but fighting — including a critical struggle for Mariupol — continues.

Should the city hold strong, or potentially fall, the outcome of the war could quickly follow, Arestovych said, as Ukrinform reported.

"They understand this," the advisor said, speaking of both countries, per the report. "On the one hand, it gives us hope in the area of Kyiv, Chernihiv, Sumy region, Kharkiv region that we will get rid of the enemy there, we will repel it from there. Secondly, it means a possible, potential deterioration or a sharp deterioration of the situation around Mariupol and in the JFO area."

"But, the next week or two will be uneven. There will be reports that we are winning, counterattacking and repelling in some areas. We are liberating our lands from the enemy," he added via Ukrinform. "However, there will also be information that in some parts of the front, particularly in the east, the situation is complicated. You need to be emotionally, organizationally and consciously ready for this."

Ukrainian President Volodymyr Zelenskyy and Russian President Vladimir Putin are far apart at the negotiating table with both sides requesting concessions deemed non-starters by the other side which could be an advantage to Putin, experts tell Fox News.

Rebekah Koffler, a former U.S. intelligence agent and author of "Putin's Playbook: Russia's Secret Plan to Defeat America," told Fox News Digital that Ukraine’s desire for a security agreement with other countries as a component of ending the war is a demand Russia will not agree to.

Read more: Wide rift in Russia, Ukraine negotiations could mean drawn out war that favors Putin: experts say

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