LONDON — Three European leaders staged a defiant present of help for Ukraine on Tuesday, touring to its besieged capital, Kyiv, at the same time as a relentless Russian artillery bombardment left condo towers within the metropolis ablaze, forcing terrified residents to flee into the road with solely the garments on their backs.

The dramatic go to by the prime ministers of Poland, the Czech Republic and Slovenia, which unfolded in tight secrecy as they crossed the Ukrainian border by prepare after daybreak, was a strikingly private gesture. Nevertheless it caught different European leaders off guard, angering some and baring uncomfortable divisions in how finest to display Western solidarity with Ukraine.

It additionally got here as President Vladimir V. Putin of Russia disparaged the second consecutive day of negotiations with Ukraine, undercutting the faint glimmers of hope raised from talks the day earlier than that each side had been on the lookout for a option to halt the battle.

The Kremlin slapped retaliatory sanctions on President Biden and different senior American officers. Mr. Biden introduced his personal plans to journey to Europe subsequent week to showcase the unity of the NATO alliance within the face of Russian aggression.

A spokesman for Poland’s prime minister, Mateusz Morawiecki, mentioned the three guests had been “de facto” representing the European Union in Ukraine. In Brussels, nonetheless, officers mentioned the trio didn’t have the E.U.’s blessing, and a few European diplomats complained that the journey was too dangerous, given the Russian forces encircling Kyiv.

Others mentioned they admired the audacity of the group, which additionally included Prime Minister Petr Fiala of the Czech Republic and Prime Minister Janez Jansa of Slovenia, casting it as a robust image of the backing for Ukraine amongst international locations on Europe’s jap flank, the place the specter of Russian aggression looms bigger than in Paris or London.

Nonetheless, for all of the symbolism of standing shoulder-to-shoulder with Ukraine’s leaders beneath the specter of Russia’s rockets, Ukraine was dealing with the devastating barrage largely by itself. The mayor of Kyiv, Vitali Klitschko, imposed a 35-hour curfew, beginning on Tuesday night, which instructed the capital was coming into an much more troublesome part of its grinding wrestle to carry off Russian troops and tanks.

“That is their try and annihilate the Ukrainian individuals,” President Volodymyr Zelensky of Ukraine mentioned in an emotional video tackle to the Canadian Parliament, repeating his plea for NATO to implement a no-fly zone over the nation. “It’s an try and destroy our future, our nation, our character.”

Mr. Zelensky requested the lawmakers to think about if the CN Tower in Toronto had been shelled just like the towers in Kyiv. His language has grow to be extra pointed, even scolding, with every speech to a Western viewers, revealing his frustration with leaders who’ve resisted extra direct army involvement out of worry that it might entangle them in a wider battle with Russia.

The Ukrainian chief, who has grow to be a hero to many within the West, is scheduled to talk through video to Congress on Wednesday, the place he’s anticipated to amplify his pleas for extra assist and improve the stress on the US and its allies.

On Tuesday night, the Polish state broadcaster carried video of the Czech, Slovenian and Polish leaders assembly Mr. Zelensky and different officers throughout an extended desk, with Ukraine’s blue-and-yellow flag behind them.

“They’re right here to help us,” Mr. Zelensky mentioned at a information briefing after the assembly, which additionally was proven on Ukrainian tv. “It’s a nice, brave, proper, pleasant step. I’m assured that with such buddies, such international locations and neighbors and companions, we are able to actually win.”

{A photograph} posted earlier on Mr. Morawiecki’s Twitter account confirmed the three males poring over a map, seated in what seemed to be a prepare carriage en path to the Ukrainian capital.

“It’s right here, in war-torn Kyiv, that historical past is being made,” Mr. Morawiecki mentioned within the Twitter submit. “It’s right here, that freedom fights towards the world of tyranny. It’s right here that the way forward for us all hangs within the balanc

The White Home introduced that Mr. Biden would fly to Brussels for a unprecedented summit assembly of NATO on March 24. That will lead to additional financial and army support for Ukraine however will doubtless fall in need of Mr. Zelensky’s request for a no-fly zone. Administration officers declined to say whether or not Mr. Biden deliberate to fulfill with the Ukrainian president, whom he has known as a hero. However they mentioned Mr. Biden could go on to someplace in Japanese Europe to fulfill with refugees streaming out of Ukraine.

The river of individuals fleeing the battle continued unabated on Tuesday, as Russia claimed to have seized management of the strategic Kherson area within the south. Russian forces saved up their pounding of civilian targets in Kyiv, the place Ukrainian troops had been fortifying intersections with sandbags, tires, and iron spikes.

A pre-dawn rain of rockets on Kyiv shattered home windows, left craters in buildings, and turned a 16-floor condo home right into a towering inferno. The fireplace unfold rapidly after a missile struck the constructing, blowing a jagged gap at its entrance. Firefighters rescued residents from home windows by ladder by billowing smoke. By midafternoon, they’d carried out two our bodies encased in black luggage.

“I got here out with nothing,” mentioned Mykola Fedkiv, 85, a retired geologist. “I left every part, my phone, my medicines, every part.”

When the missile struck, Mr. Fedkiv fled his Twelfth-floor condo and made his approach down the steps. He climbed by the blasted entrance corridor and located himself within the bomb crater. Individuals pulled him out by his arms. He stood exterior for hours, hoping to re-enter his condo to gather private paperwork. Requested the place he deliberate to remain the night time, he responded, “God is aware of.”

Circumstances had been much more determined within the coastal metropolis of Mariupol, which has been pummeled by Russian forces in a two-week siege that has left some residents crushed within the rubble and lots of others dying in a winter freeze with no warmth, meals, or clear water. Officers can now not account for the variety of useless and lacking.

Formally, 2,400 civilians killed in Mariupol have been recognized, however Pyotr Andryushchenko, an adviser to town authorities, mentioned he believed the toll was far increased, probably as many as 20,000. Ukrainian estimates of the variety of individuals trapped have ranged from 200,000 to 400,000.

Mr. Andryushchenko mentioned 2,000 autos had managed to flee Mariupol on Tuesday and that one other 2,000 had been packed and able to go away. Officers informed civilians to “delete all messages and pictures from telephones” in case Russian troopers searched them for indicators of help for Ukrainian forces.

The perils of reporting correct info from Ukraine’s fight zones had been additional underscored Tuesday with information {that a} Fox Information cameraman and a Ukrainian colleague had been killed in an assault on Monday exterior Kyiv — elevating to not less than three the variety of journalist fatalities in Ukraine up to now few days.

In Kherson, a southern metropolis beneath Russian occupation, the mayor mentioned that members of Russia’s nationwide guard had been rounding up activists who opposed Russia’s presence, probably attempting to recruit them by coercion.

“They’re all within the metropolis, within the jail,” the mayor, Igor Kolykhaev, wrote in a number of textual content messages, referring to the activists. Russian troops, he mentioned, “accumulate them, maintain them, work them over and launch them.”

Kherson was the primary main metropolis to fall to Russian forces after the Feb. 24 begin of the invasion. Though Kremlin officers had predicted that the Ukrainian individuals would welcome their “liberation” by Russian troops, residents of Kherson have been defiant, repeatedly gathering within the central sq. to protest the Russian presence, even when Russian troops hearth into the air to disperse them.

Russia claimed to have captured the complete Kherson area, doubtlessly strengthening its potential to push west towards the strategic port cities of Mykolaiv and Odessa. A senior Ukrainian army official, talking on the situation of anonymity, confirmed that Russian forces had been answerable for a lot of the Kherson area, however mentioned Ukrainian forces had been attacking their positions and inflicting losses.

Negotiations through video hyperlink between Russia and Ukraine continued for a second day on Tuesday, although Mr. Putin doused prospects of any imminent breakthrough. In a telephone name with the president of the European Council, Charles Michel, Mr. Putin complained that “Kyiv isn’t demonstrating a severe angle towards discovering mutually acceptable options,” based on the Kremlin.

Mr. Putin additionally continued to wrestle within the info battle with Ukraine. On Tuesday, President Emmanuel Macron of France mentioned his nation may supply diplomatic “safety” to a Russian state tv worker who was detained and fined over an on-air antiwar protest on Monday.

The worker, Marina Ovsyannikova, burst onto the reside broadcast of Russia’s most-watched information program on Monday night, yelling, “Cease the battle!” and holding an indication that learn, “They’re mendacity to you right here.”

Russia additionally confronted additional isolation from Britain, which imposed sanctions on greater than 370 individuals it labeled oligarchs, political allies of, or propagandists for Mr. Putin. Amongst these blacklisted: Dmitri A. Medvedev, the previous president of Russia; Mikhail Mishustin, the present prime minister; and Mikhail Fridman, the billionaire founding father of Alfa Financial institution, one of many nation’s largest non-public banks.

Russia, for its half, mentioned it had sanctioned 13 People together with Mr. Biden, Secretary of State Antony J. Blinken and Protection Secretary Lloyd J. Austin III in response to American sanctions towards Mr. Putin and different officers. Additionally on its record was Hillary Rodham Clinton, the previous secretary of state, and Mr. Biden’s son, Hunter Biden.

Mr. Biden’s press secretary, Jen Psaki, shrugged off the information, suggesting in jest that the Kremlin’s announcement may need missed its meant mark. The president, Ms. Psaki mentioned, is a “junior, so they could have sanctioned his dad by mistake.”

Mark Landler reported from London, and Matina Stevis-Gridneff from Brussels. Reporting was contributed by Carlotta Gall and Lynsey Addario from Kyiv, Ukraine; Michael Schwirtz from Odessa, Ukraine; Anton Troianovski from Istanbul; Andrew Higgins from Warsaw; Ian Austen from Ottawa; Steven Erlanger from Brussels; David E. Sanger and Glenn Thrush from Washington; and Michael M. Grynbaum from New York.