In just over a month, President Donald Trump has overturned old certainties about U.S. reliability as a security partner, as he embraces Russia and withdraws American support for Ukraine.

On Monday, Trump ordered a pause to U.S. military supplies to Ukraine as he sought to press President Volodymyr Zelenskyy to engage in negotiations to end the war with Russia, bringing fresh urgency to the EU summit in Brussels.

“Europe faces a clear and present danger on a scale none of us have seen in our adult lifetime. Some of our fundamental assumptions are being undermined to their very core,” European Commission President Ursula von der Leyen warned in a letter to the EU’s 27 leaders, who will consider ways to access more money for defense spending and ease restrictions on it.

But perhaps the biggest challenge for the EU on Thursday will be to take a united stance at a moment when it’s fractured, since much of what the bloc does requires unanimous support.

Focus is Europe’s security

Whatever happens, the meeting is not expected to address Ukraine’s most pressing needs.

It is not aimed at urgently drumming up more arms and ammunition to fill any supply vacuum created by the U.S. freeze. Nor will it unblock the estimated 183 billion euros ($196 billion) in frozen Russian assets held in a Belgian clearing house, a pot of ready cash that could be seized.

Ukraine’s armed forces, meanwhile, are still battling to slow Russia’s advances along the 1,000-kilometer (600-mile) front line, especially in the eastern Donetsk region. Tens of thousands of soldiers and more than 12,000 Ukrainian civilians have been killed.

The focus of Thursday’s summit will be finances, and how to set the EU up as quickly as possible to provide for its own security, and help Ukraine, while breaking with decades of dependence on the U.S. defense umbrella.

“In view of the increasing threat situation, it is clear to us that Europe … must now very quickly make very big efforts, very quickly, to strengthen the defense capability of our country and the European continent,” Germany’s likely next chancellor, Friedrich Merz, said Tuesday.

The prospective partners in Germany’s next government are seeking to loosen the nation’s rules on running up debt to allow for higher defense spending.

A call for Europe to increase its defense spending

NATO Secretary-General Mark Rutte — who fears that Russia’s armed forces might be capable of launching an attack on another European country by the end of the decade — has warned that U.S. allies will have to spend more than 3% of gross domestic product on their military budgets.

The Trump administration is demanding that the Europeans spend as much as 5%, well beyond the NATO benchmark of at least 2%. Seven European allies still fall short of even that target. The U.S. spends around 3.4%, according to NATO figures, and a Pentagon audit that could reduce that is pending.

Von der Leyen has proposed that the EU’s executive branch, the European Commission, raise up to 150 billion euros ($161 billion) on financial markets that would be loaned to member countries buy new military equipment for themselves, or to send to Ukraine.

The commission would also aim to free up funds from other sectors of the bloc’s massive long-term budget and to relax its stringent debt rules so that each country could invest up to 1.5% more of their GDP on defense, should they want to.

The leaders will also discuss whether to place more arms contracts with Ukraine’s defense industry, and to help integrate it into the European industrial network. Production costs in Ukraine are much lower, providing a relatively fast way to supply more arms and ammunition.

It’s an approach that Zelenskyy has praised.

“Last year alone, thanks to Ukrainian and partner efforts, we produced over 1.5 million drones of various types. Ukraine is now the world leader in drone warfare. This is our success. But it’s also your success,” he said earlier this month at the Munich Security Conference.

Possible EU support for a future force to police any peace agreement in Ukraine will also be weighed. Britain and France are leading that effort, which could involve several other European countries.

EU faces major challenges

The summit comes as the EU is arguably at its weakest point, fragmented by the steady rise of a hard right that is often pro-Russian.

Hungary and Slovakia have routinely undermined support for Ukraine. Hungary is threatening to veto a joint statement drafted for Thursday’s summit but would not be able to block any major security or financing decisions.

Meanwhile, many larger countries face uncertainties at home. Germany will soon have a new chancellor, but France’s latest government is fragile, and Spain relies on small parties to keep its coalition intact.

Poland offers strong leadership under Prime Minister Donald Tusk, however a presidential election looms and a right-wing candidate is well placed. The Dutch cabinet dominated by hard-right leader Geert Wilders is shaky.