Leaders have worked hard to get on the right side of 'unpredictable' Trump - precisely for moments like today

Truly, this is a moment as important as it is unusual. History does not provide us a guide here.

Never before have we seen so many world leaders gather at such short notice for a meeting like this at the White House, and with a president as consequential as he is unpredictable.

The speed with which it has been organised is remarkable. A diplomatic source has framed the hasty gathering as "organic"; the obvious next step after the Alaska summit, the source said.

The Europeans were not in the room for that. Today, they will dominate the room.

Is there a risk Donald Trump will feel encircled? I don't think so. More likely, he will enjoy the moment, seeing himself as the great convener. And on that, he'd be right.

Whether his diplomatic process has been cack-handed or smart - and the debate there will rage on - there is no question he has created this moment of dialogue.

It was the unfolding, or unravelling, of another White House moment, back in February, which gives some key context for the day ahead.

That Trump-Zelenskyy Oval Office meltdown was a reality check for European leaders.

We all watched Trump and his vice-president, JD Vance, slam the Ukrainian leader. It was excruciating but it was also instructive because, beyond the shouting, positions and attitudes were made clear.

That February meeting provided everyone with a crystallising sense of precisely who they were dealing with.

Since then, Europe and its key leaders have moulded and shifted their positions. Collectively they have transformed their own defence spending - recognising the necessity to stand on their own. And individually they have sought, urgently, to forge their own relationships with the US president.

Each of the leaders here today has worked hard (cringingly so, some might say) to get on the right side of Trump.

Whether it be Starmer and his state visit, Stubb and his golfing skills, Meloni and her Trump-aligned politics, or Rutte and his "daddy" comments, they have all appealed in different ways to Trump. They have done so precisely for moments like today.

In the hours ahead, we can expect Trump and Zelenskyy to meet with their respective delegations. We will probably see them together in the Oval Office. Brace for no repeat of February; Zelensky knows he played that badly.

Analysis and explainers:
How a chaotic 24 hours unfolded ahead of talks
Why Zelenskyy is taking a posse of leaders for talks

A repeat is unlikely not least because, in a typically Trumpian way, the American president appears to be agreeing now to the very thing he chastised Zelenskyy for requesting back in February - security guarantees before the war stops.

There will be plenty to look out for in the day ahead.

With Trump, the trivial matters as much as the detail, and very often the trivial can impact the detail. So will Zelenskyy wear a suit and tie, or at least a jacket? Remember the furore over his decision to stick to his war-time combat gear in February.

After that bilateral meeting, the wider meeting is expected. The central aim of this from a European perspective will be to understand what Trump is prepared to do in terms of guaranteeing Ukrainian security, and crucially what he and Putin discussed and agreed.

Is Putin really willing to accept some sort of American-European security pact for Ukraine? That sounds like NATO without the membership, so would that really fly with the Russian president?

Beyond that - what precisely did Trump and Putin discuss in terms of territorial swaps (more accurately described as control swaps because Ukraine would be negotiating away its own land)?

There is a concern that intentional ambiguity might allow for a peace deal. The different sides will interpret the terms differently. That could be fine short-term, providing Trump with a quick fix, but longer term it could be unsustainable and dangerous.

So above all, the European leaders' tone to Trump will be one of flattery framed by a gentle warning.

They'll tell him that he created this moment for peace; that it is his peace and that they want to work with him to keep it (and thus cement his legacy).

But to do that, they will tell him, they need his continued commitment to them; to Europe, not capitulation to Russia.

(c) Sky News 2025: Leaders have worked hard to get on the right side of 'unpredictable' Trump - precise