Is This the Breaking Point for Trump and Zelensky?

Where the two presidents' war of words will end is anybody's guess. But if it continues, it could threaten the crucial operational help that Ukraine still gets from the United States.

This time, the rupture feels real.

President Trump has long made no secret of his disdain for President Volodymyr Zelensky of Ukraine and his affinity with President Vladimir V. Putin of Russia. But Mr. Zelensky has always managed to hold on to some form of American support against Russia, going along with fruitless U.S.-led peace talks and heaping thanks and flattery on Mr. Trump for his "strong leadership."

Now, in the run-up to midterm elections seen as a referendum on Mr. Trump's presidency, their relationship seems close to a breaking point. The split poses risks to the Trump administration but more critically to Ukraine, whose military still gets crucial operational help from the United States.

For Kyiv, the blows came one after the next in just one very bad week.

Mr. Trump blamed the war launched by Russia against Ukraine almost five years ago for rising diesel prices, instead of what energy experts call the real cause: the war that Mr. Trump launched against Iran. He temporarily lifted U.S. sanctions on Russian diesel sales in what is likely to be a failed attempt to lower those prices. He unilaterally declared an "ENERGY CEASEFIRE" in the war that only helped Russia and hurt Ukraine. And he called for a new Ukrainian president.

By midweek, the Ukrainian military was reporting sudden unexplained restrictions on its use of Starshield, a military version of the satellite internet system Starlink that is crucial to Ukraine's battlefield communications. Elon Musk, the on-again, off-again good friend of Mr. Trump and the chief executive of SpaceX, which operates Starlink, suggested that only the U.S. military and ultimately Mr. Trump could limit Starshield's usage. Mr. Musk then also called for a new Ukrainian president.

After initially holding back, a visibly angry Mr. Zelensky said he felt betrayed as Mr. Trump openly sided with a Russian leader who is killing Ukrainian civilians by the dozen. Defying Mr. Trump's cease-fire declaration, Mr. Zelensky said Ukraine would restart its attacks on Russian oil refineries. Asked by the journalist Piers Morgan to clarify whether he believed Ukraine was "losing" the United States, Mr. Zelensky replied simply: "Yes."

Mr. Trump then told Newsmax that "Zelensky is not a good guy for us to deal with."

On Friday in Belgium, Mr. Zelensky seemed to go further. When asked if he was being treated as a scapegoat for Mr. Trump's problems, Mr. Zelensky, a former comedian with excellent comic timing, gave a sideways smile and paused at length. Everyone laughed. Then he leaned into the microphone and said: "This is my answer."

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Where the war of words will end is anybody's guess. But if it continues, it will help Russia and hurt the Trump administration, Ukraine and Kyiv's European allies, according to analysts.

"It is a lose-lose situation," said Balazs Jarabik, a former European Union diplomat in Kyiv who now works at R. Politik, a political analysis firm. "It's bad for Trump, I think. It's bad for Zelensky, obviously. It's bad for the Europeans."

The worst case for Ukraine would be if Mr. Trump and his Defense Department were to suspend aid to the Ukrainian military. Kyiv is hoping that such a step would be too politically damaging for Mr. Trump, as he faces criticism from some in his own party over his treatment of Ukraine.

Kyiv relies on the Pentagon-funded Starshield internet network along the front line, as well as on military intelligence that alerts the country to incoming missile strikes and helps it with targeting for its own midrange strikes.

Ukraine also relies on the United States for weapons that it purchases with the help of allies, such as spare F-16 parts, radiation-seeking missiles and Patriot interceptor missiles, the only weapon Ukraine can access that can knock down Russian ballistic missiles.

A loss of this assistance would hurt the Ukrainian military just as it has been performing well against the Russians on the front line. It would also hurt Ukrainian cities that are under constant missile and drone attack and cause more Ukrainian civilians to die, analysts said.

The United States used to be Ukraine's No. 1 ally in this war. But then Mr. Trump came into office. He said the days of isolating Russia were over, blamed Ukraine for being invaded and upended generations of U.S. foreign policy. Then came a disastrous meeting between Mr. Zelensky and Mr. Trump at the White House, when Mr. Zelensky was berated for not wearing a suit and not being grateful enough for American help.

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While Mr. Zelensky repaired that rift, the United States stopped donating weapons to Ukraine, instead requiring Kyiv and its Western allies to pay for them. Since then, Ukraine has significantly built up its own defense production, softening the blow as the United States has pulled back -- and giving Mr. Zelensky more room to speak out.

"The leverage that Trump has with not giving Ukraine things anymore is very limited," said Nico Lange, a former German Defense Ministry official who is now a senior fellow at the Munich Security Conference. "There is still a public impression, and also the impression maybe with Trump, that Ukraine will lose the war if the U.S. can't help anymore. But this is not true."

Still, while European countries provide some intelligence to Ukraine, there's no substitute for the U.S. intelligence that gives early warnings for cruise missile strikes from ships in the Black Sea or ballistic missile attacks, Mr. Lange said. If Ukraine gets no advance warning of incoming ballistic missiles and has no Patriots to knock them down, Russia will be able to strike with impunity.

"We will die because we won't receive warnings about ballistic missile attacks," said Oleh Katkov, a military analyst and the editor in chief of AIN, a Ukrainian media outlet that covers defense and technology. "That means we won't be able to get to shelters in time. And we won't have the means to shoot down those missiles ourselves."

Solomiia Bobrovska, a member of the Ukrainian Parliament's defense committee and the deputy head of the Ukrainian delegation to NATO, said she worried that the United States would stop providing Patriot interceptors. The worldwide supply of the missiles has been depleted, largely because of the war in Iran, but Ukraine still receives a small number every month.

Ms. Bobrovska also said that Ukraine and its allies needed to find alternatives to U.S. help for the future. She added that Ukraine would not stop fighting, regardless of what happened. "If you want to hear from me the words 'peace' and 'capitulation,' it's not an option at all," she said.

Ukraine got a glimpse this week of what could happen if the United States stopped helping.

Ukrainian officials said that Ukraine received no advance notice from its partners -- code language for the United States -- for two waves of missile attacks against Kyiv on Tuesday and Wednesday. Those missiles hit just as air-raid alarms came on.

It's not clear why Ukraine did not get any notice. It might have been because those missiles were S-400s, which travel short distances extremely quickly, which often doesn't allow for much warning. Ukrainian officials said they received notice of other ballistic attacks.

Then came the Starshield disruptions, which Ukrainian soldiers said interfered with drone launches and a range of other operations. A bipartisan group of U.S. senators has demanded an investigation.

The next couple of weeks could give a sign of what might happen next in the Trump-Zelensky relationship, analysts said.

"We have to see what's going to happen up to the midterms," said Harry Nedelcu, a senior director at Rasmussen Global, a European political advisory firm. "We have to see how Trump will play this out. On one hand, he wants to show he's bringing gas prices down. On the other, he's facing criticism from his own ranks. Geopolitically, however, of course it's a stab in the back. A geopolitical betrayal."

Constant Méheut, Jeanna Smialek, Oleksandra Mykolyshyn and Nataliia Novosolova contributed reporting.