THE HAGUE, Netherlands >> NATO leaders agreed on a massive hike in defense spending Wednesday after pressure from U.S. President Donald Trump, and expressed their “ironclad commitment” to come to each other’s aid if attacked.

The 32 leaders endorsed a final summit statement saying: “Allies commit to invest 5% of GDP annually on core defense requirements as well as defense- and security-related spending by 2035 to ensure our individual and collective obligations.”

The show of unity vindicated NATO Secretary-General Mark Rutte’s billing of the summit as “transformational,” even though it papered over divisions.

Trump called the spending boost “something that no one really thought possible. And they said, ‘You did it, sir. You did it.’ Well, I don’t know if I did it, but I think I did.”

Spain had already officially announced that it cannot meet the target, and others have voiced reservations, but the investment pledge includes a review of spending in 2029 — after the next U.S. presidential elections — to monitor progress and reassess the security threat posed by Russia.

The leaders also underlined their “ironclad commitment” to NATO’s collective security guarantee — “that an attack on one is an attack on all.” Ahead of the summit, Trump had again raised doubts over whether the United States would defend its allies.

“Together, allies have laid the foundations for a stronger, fairer and more lethal NATO,” Rutte told reporters after chairing the meeting in The Hague. “This will fuel a quantum leap in our collective defense.”

The spending hike requires each countries to spend billions of dollars. It comes as the United States — NATO’s biggest-spending member — shifts its attention away from Europe to focus on security priorities elsewhere, notably in the Middle East and Indo-Pacific.

Spain had called the new spending target and 2035 deadline “unreasonable.” Belgium signaled that it would not get there either, and Slovakia said it reserves the right to decide its own defense spending.

Prime Minister Pedro Sánchez stood conspicuously aside from other leaders in the summit family photo. After the meeting, he said that Spain can execute NATO’s defense plans by spending only 2% of gross domestic product on defense.