The day began with the same cordial routine the White House reserves for visiting foreign dignitaries.

Ukraining President Volodymyr Zelensky was welcomed by President Donald Trump at the door of the West Wing with an honour guard, and the leaders shook hands politely.

We were in the Oval Office as part of Ukrainian media pool, witnessing the well-rehearsed formalities.

Zelensky presented President Trump with the championship belt of Ukrainian boxer Oleksandr Usyk.

Trump complimented Zelensky’s clothing.

So far, so diplomatic.

But minutes later, what erupted was unprecedented to say the least. The genial tone devolved into acrimony and chaos. Voices were raised, eyes-rolled, aspersions cast – and all in front of the world’s TV cameras.

The American president and the vice-president berated the visiting leader, accusing Zelensky of not being grateful enough for US support that has sustained Ukraine’s war effort.

Tensions flared when vice-president JD Vance told Zelensky that the war had to be ended through diplomacy.

What kind of diplomacy, Zelensky replied.

Talking over the Ukrainian president, Vance told the visiting leader it was “disrespectful” for him to come to the Oval Office and make his case in front of the American news media and demanded that he thank Trump for his leadership.

Journalists in the room watched with gaping mouths, as an extraordinary exchange followed.

“You’ve done enough talking. You’re not winning this,” Trump told him at one point. “You gotta be thankful. You don’t have the cards.”

“I’m not playing cards,” Zelensky replied. “I’m very serious, Mr President. I’m the president in a war.”

“You’re gambling with World War Three,” Trump responded. “And what you’re doing is very disrespectful to the country, this country, that’s backed you far more than a lot of people said they should have.”

Vance retorted: “Have you said ‘thank you’ once this entire meeting? No.”

Ukraine’s ambassador to the US watched with her head in her hands.

The atmosphere had shifted entirely – and all out in the open.

Our American colleagues remarked that they had never seen anything like it. “A scene like this was simply unimaginable in the White House,” one told me.

As reporters exited the Oval Office, many stood still, in a state of shock. In the White House briefing room, where the exchange was replayed shortly afterwards, the rest of the media who hadn’t been in the room watched in disbelief.

Confusion ensued. There were immediate questions about whether the planned news conference would go ahead – or if the much-anticipated deal between the US and Ukraine over mineral resources would even be signed.

Minutes later, Trump posted on Truth Social that Zelensky could “come back when he is ready for peace”.

The news conference and deal-signing ceremony – set to take place in the East Room of the White House – was officially cancelled.

Soon after Zelensky strode out and into a waiting SUV, as his ambassador trailed behind him.

They pulled away as the world was only beginning to digest an extraordinary moment.

Despite the full-blown argument, there may still be a minerals deal sooner or later.

But one thing is certain: this visit by Zelensky will be remembered for entirely different reasons.

The world saw first-hand how negotiations between the US and Ukraine are unfolding: they are difficult, emotional, and tense.

It was clear that this was a tough negotiation for both parties.

The gift of Ukrainian boxer Oleksandr Usyk’s belt certainly didn’t save the situation. And after this bout at the White House, the real question now is what this means for the war in Ukraine – and Zelensky’s own future.

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