US response to Russian ballistic missile strike 'weak,' Zelenskyy says

LONDON -- Ukrainian President Volodymyr Zelenskyy called for "sufficient pressure on Russia" after a day of missile and drone strikes that killed at least 23 people and as Kirill Dmitriev -- the CEO of Russia's Direct Investment Fund and an envoy of President Vladimir Putin -- met with officials in the U.S.

Eighteen people were killed -- among them nine children -- in a Russian ballistic missile attack on the central city of Kryvyi Rih on Friday, Oleksandr Vilkul -- the head of the local defense council -- said in a post on Telegram. Another 56 people were injured in the strike, Vilkul said.

U.S. Ambassador to Ukraine Bridget Brink wrote in a post to X, "Horrified that tonight a ballistic missile struck near a playground and restaurant in Kryvyi Rih. More than 50 people injured and 16 killed, including 6 children. This is why the war must end."

Zelenskyy said in a Saturday morning post to Telegram that the American reaction was inadequate.

"Unfortunately, the reaction of the American Embassy is unpleasantly surprising: such a strong country, such strong people -- and such a weak reaction," he said. "They are even afraid to say the word 'Russian' when talking about the missile that killed children."

Russia's Defense Ministry said the strike targeted a meeting of Ukrainian commanders and "Western instructors" at a restaurant in the city. Ukrainian officials disputed the Russian justification.

Zelenskyy said in a statement on Friday evening that the strike in Kryvyi Rih -- his home town -- hit "an area near residential buildings: hitting a playground and regular streets," describing those responsible for the attack as "inhuman."

The president also reported a strike drone attack in the northeastern city of Kharkiv which killed five people and wounded 34 others. Another attack in the southern city of Kherson "hit an energy facility -- the Kherson thermal power plant," Zelenskyy wrote.

"Yes, the war must end," Zelenskyy wrote in his Saturday morning statement. "But in order to end it, we must not be afraid to call a spade a spade. We must not be afraid to put pressure on the only one who continues this war and ignores all the world's proposals to end it."

"We must put pressure on Russia, which chooses to kill children instead of a ceasefire. We must introduce additional sanctions against those who cannot exist without ballistic strikes on neighboring people. We must do everything possible to save lives."

Russia and Ukraine both launched more strikes overnight into Sunday morning. Ukraine's air force reported 92 drones entering the country overnight, of which 51 were shot down and 31 lost in flight without causing damage. The air force reported damage in the Sumy, Dnipropetrovsk, Kyiv and Zhytomyr regions.

Russia's Defense Ministry said its forces shot down 49 Ukrainian drones overnight.

Artyom Zdunov -- the head of the Mordovia region, to the southeast of Moscow -- said in a Telegram post that a drone targeted an industrial site there. "Operational and emergency services are working on the territory," he wrote. "According to preliminary information, there are no casualties."

Andriy Kovalenko -- the head of the Counter-Disinformation Center operating as part of Ukraine's National Security and Defense Council -- wrote on Telegram that a strike by "unknown drones" targeted a military industrial complex in Saransk, the capital of Mordovia. Kovalenko said goods produced there are used "in control, communication and data transmission systems, in particular -- in the deployment of secure communication channels for the Russian army and in the control of drones."

Both Ukraine and Russia have accused the other of continuing strikes on energy facilities despite the U.S.-brokered partial ceasefire that all parties said they agreed to last month. The agreement was intended to freeze all attacks on energy infrastructure and in the Black Sea, Kyiv, Moscow and Washington said.

Zelenskyy on Friday again accused Russia of violating the terms of the deal.

"These strikes cannot be accidental," the president said. "The Russians know exactly that these are energy facilities and that such facilities should be protected from any attacks under what Russia itself promised to the American side."

"Every Russian promise ends with missiles or drones, bombs or artillery," he continued.

"Diplomacy means nothing to them. And that's why pressure is needed -- sufficient pressure on Russia so they feel the consequences of every lie of theirs, every strike, every single day they take lives and prolong the war."

Earlier this week, Russian Foreign Minister Sergei Lavrov also accused Ukraine of violating the partial ceasefire. Moscow passed information about the alleged violations to the U.S., the foreign minister said. On Saturday, Russia's Defense Ministry alleged 14 Ukrainian attacks on Russian energy infrastructure over the previous 24 hours.

Secretary of State Marco Rubio said Friday that President Donald Trump's administration is waiting to see whether Moscow is serious about reaching an agreement to end its 3-year-old full-scale invasion of Ukraine.

Noting Dmitriev's meetings in Washington this week, Rubio said, "He'll take some messages back" to Moscow. "And the message is, the United States needs to know whether you're serious or not about peace. Ultimately, Putin will have to make that decision."

"If there's a delay tactic, the President's not interested in that," Rubio said. "If this is dragging things out, President Trump's not going to fall into the trap of endless negotiations about negotiations," he added.

Washington's messages to the Kremlin via Dmitriev were not "threatening," Rubio said, but were instead "more of an explanation of…our timeline," which Rubio said was a matter of "weeks."

"It's pretty short. At the same time as we now have seen, members of Congress have begun to file bills to increase sanctions. So there is going to be growing pressure from Capitol Hill to impose sanctions," Rubio continued. "All these factors have been explained in the nicest way possible. Hopefully he'll take that message back to Moscow."

As to potential violations of the partial ceasefire, Rubio suggested some incidents were to be expected. "I think there's things they're not striking that they were before," he said.

But "if all of a sudden we wake up tomorrow and the Russians are launching a massive offensive, then I think that's a pretty clear sign they're not interested in peace," Rubio added. "That hasn't happened yet."

ABC News' Ellie Kaufman, Christopher Boccia, Tanya Stukalova and Oleksiy Pshemyskiy contributed to this report.