YEREVAN, Armenia (AP) — European leaders on Monday said that President Donald Trump's snap decision to pull thousands of U.S. troops out of Germany came as a surprise but is a fresh sign that Europe must take care of its own security.

The Pentagon announced last week that it would pull some 5,000 troops out of Germany, but Trump told reporters on Saturday that "we're going to cut way down. And we're cutting a lot further than 5,000."

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He offered no reason for the move, which blindsided NATO, but his decision came amid an escalating dispute with German Chancellor Friedrich Merz over the U.S.-Israeli war on Iran, and Trump's anger over European allies' reluctance to get involved in the conflict in the Middle East.

Asked about the American decision, Norwegian Prime Minister Jonas Gahr Støre said: "I wouldn't exaggerate that because I think we are expecting that Europe is taking more charge of its own security.

"I do not see those figures as dramatic, but I think they should be handled in a harmonious way inside the framework of NATO," he told reporters in Yerevan, Armenia, where European leaders held a summit.

British Prime Minister Keir Starmer said that "there needs to be a stronger European element in NATO, I have no doubt, about that." He told his European partners that there is "more tension" in some of their international alliances "than there should be, and it is very important that we therefore face up to this."

Taken by surprise

The European Union's foreign policy chief, Kaja Kallas, said "there has been a talk about withdrawal of U.S. troops for a long time from Europe. But of course, the timing of this announcement comes as a surprise."

"I think it shows that we have to really strengthen the European pillar in NATO," she said.

Asked whether she believes that Trump is trying to punish Merz, who said that the U.S. has been humiliated by Iran in talks to end the war, Kallas said: "I don't see into the head of President Trump, so he has to explain it himself."

Merz did not attend the European Political Community summit of around 30 European leaders, plus Canadian Prime Minister Mark Carney, in Armenia. But his spokesman Stefan Kornelius, asked in Berlin whether the U.S. can still be relied on as a military partner, replied: "Absolutely."

He said that the trans-Atlantic alliance has grown over decades and argued that "we have a very resilient and broad relationship." But on what Trump meant when he said the troop cuts would exceed 5,000, Kornelius said: "You'd have to ask the American government."

In response to Trump's threats over the last year, European countries and Canada have increased defense spending and military recruitment efforts.

NATO seeks clarity

Over the weekend, NATO spokesperson Allison Hart said officials at the 32-nation military alliance "are working with the U.S. to understand the details of their decision on force posture in Germany."

WATCH: Germany builds up its military to prepare for a potential future without U.S. support

European allies and Canada have known since just after he came to office again last year that Trump would pull troops out of Europe, some already left Romania in October, but U.S. officials had pledged to coordinate any moves with their NATO allies to avoid creating a security vacuum.

NATO Secretary-General Mark Rutte played down the move, saying that "there has been at this point disappointment on the U.S. side" about European support for the war on Iran.

Notably, France, Spain and the U.K. have declined to give U.S. forces free rein to use bases on their territory to attack Iran. Spain has denied them the use of its airspace and bases for the war.

But Rutte, who has championed Trump's leadership at NATO despite the U.S. president's criticism of the majority of the allies, said: "I would say the Europeans have heard a message. They are now making sure that all the bilateral basing agreements are being implemented."

Iran and trade trouble

Rutte added that European nations "have decided to pre-position assets, key assets, close to the theater for the next phase."

He provided no details, but the Europeans have insisted they would not help police the Strait of Hormuz, a key energy trade route, until the war is over.

French President Emmanuel Macron said: "If the United States is ready to reopen Hormuz, that's great. That's what we've been asking for since the beginning." But he underlined that Europeans are not ready to get involved in any operation "that does not seem clear."

In another sign of friction with Merz, Trump has accused the EU of not complying with its U.S. trade deal and announced plans to increase tariffs next week on cars and trucks produced in the bloc to 25%, a move that would be particularly damaging to Germany, a major automobile manufacturer.

Without mentioning Trump or the United States, European Commission President Ursula von der Leyen listed recent trade deals that the bloc has sealed with Australia and India, and is now working on with Mexico.

"With like-minded friends, you have stable, reliable supply chains and Europe has the biggest network of free trade agreements," von der Leyen, who is from Germany, told reporters.

Cook reported from Brussels. Associated Press writer Geir Moulson in Berlin contributed to this report.