The public argument between US President Donald Trump and his Ukrainian counterpart was the "opposite of diplomacy", and its damage will be "hard to repair", with the test being whether Washington will stop sending weapons to Kiev, analysts said.

The meeting at the White House Oval Office on Friday between Trump — who was joined by Vice-President JD Vance — and Ukrainian President Volodymyr Zelensky developed into a shouting match while the television cameras rolled.

Trump accused Zelensky of "gambling with World War III" and claimed Ukraine lacked the "cards" to fight Russia, while Vance labeled him disrespectful and ungrateful.

Trump later declared on X.com that Zelensky is "not ready for Peace if America is involved, because he feels our involvement gives him a huge advantage in negotiations", canceling lunch and a scheduled news conference.

Zelensky departed the White House less than three hours after he arrived, and a highly anticipated rare earth minerals deal was not signed.

US State Department spokeswoman Tammy Bruce said what many saw as Trump, Vance and Zelensky sparring in public was "diplomacy in action with blunt talk and a clarity that you rarely, rarely see … part and parcel of what it means to make America great again".

"Public debates like those are the opposite of diplomacy in action. In my view, the relation had soured before the meeting, which only confirmed that fact," Stanley Renshon, a political scientist at the City University of New York, said on Saturday.

"The relation will not improve but continue as it now is," Renshon told China Daily. "All that is left to watch for now is the ongoing charade."

Cal Jillson, a political scientist and historian at Southern Methodist University in Dallas, said that inviting reporters and cameras into the Oval Office and then dressing down a "beleaguered wartime ally" is not diplomacy.

"The damage created by such a public break will be hard to repair. Trump will require more access to Ukrainian minerals; he and Vance will require that Zelensky crawl, and he seems unwilling to do that. But pressure on him will build," Jillson said in an email.

Jillson said one of the things to watch in the coming weeks would be "how fast and fully the major European states move to fill the intelligence and material gaps left as American assistance declines".

For James M. Lindsay, a senior fellow in US foreign policy and director of Fellowship Affairs at the Council on Foreign Relations, the main thing to watch for in the near term is whether Trump cuts US weapons shipments to Ukraine.

Lindsay said the "acrimonious" meeting with Zelensky that culminated in the Ukrainian president being asked to leave the White House "has no precedent", as heads of government generally do not bicker in front of the cameras.

The researcher said in a note posted immediately after Friday's meeting that although Trump said in December that he might reduce US military aid to Ukraine once in office, that has yet to happen.

"Ukraine's ability to hold off Russia depends on maintaining the flow of US weapons. Everything changes if that stops," Lindsay wrote.

"Europe cannot make up the shortfall. So while the rhetorical fireworks between Trump (and Vance) and Zelensky grab the headlines — Trump himself said that today's meeting made for 'great television' — deeds matter more than words," he added.

Early on Saturday, Zelensky took to X to do some thanking, in response to Vance, who asked him "Have you said thank you once?" in Friday's talk.

Also in the morning, Zelensky outlined the terms of the deal he is seeking, saying that he is ready to sign the minerals agreement as "a first step toward security guarantees".