WASHINGTON — President Donald Trump’s pledge to provoke a sweeping tariff fight with Europe to get his way in taking control of Greenland has left many of America’s closest allies warning of a rupture with Washington capable of shattering the NATO alliance that once seemed unshakable.

The European Union’s top official on Tuesday called Trump’s planned new tariffs on eight of its countries over Greenland a “mistake” and questioned Trump's trustworthiness. French President Emmanuel Macron said the EU could retaliate by deploying one of its most powerful economic tools, known colloquially as a trade “bazooka.”

Trump prides himself on ratcheting up pressure to try to negotiate through a position of strength. He left Washington on Tuesday — the anniversary of his inauguration — for the World Economic Forum in Davos, Switzerland, a venue that offers him the chance to defuse tensions as quickly as he stirred them up.

But European leaders — digging in and vowing to defend Denmark and its control over semiautonomous Greenland — may be trying just as hard to meet an extraordinary moment with a show of their fierce resolve.

That could hurt the chances of Trump finding a quick way to turn around the crisis. Greenland’s leader insisted on respect for its territorial integrity and called international law “not a game.”

Trump made an unusual appearance in the White House briefing room Tuesday. Asked how far he'd be willing to go to acquire Greenland, Trump said only, “You'll find out.” He also mistakenly referred to Greenland as Iceland at one point.

Still, the president predicted there could be a deal in the making. “I think that we will work something out where NATO is going to be very happy, and where we’re going to be very happy," he said, without providing specifics.

Trump said he'd been encouraged that NATO had increased military spending, but he also belittled the alliance, saying other members may not protect Washington's interests. The president suggested NATO members expect the U.S. to come to their rescue but “I just really do question whether or not they’ll come to ours.”

European Commission President Ursula von der Leyen pushed back against Trump's announcement that, starting in February, a 10% import tax will be imposed on goods from eight European nations that have rallied around Denmark. Greenland is a semiautonomous territory of Denmark, a NATO member.

“The European Union and the United States have agreed to a trade deal last July,” von der Leyen said in Davos. “And in politics as in business, a deal is a deal. And when friends shake hands, it must mean something.”

“We consider the people of the United States not just our allies, but our friends. And plunging us into a downward spiral would only aid the very adversaries we are both so committed to keeping out of the strategic landscape,” she added.

She vowed that the EU’s response “will be unflinching, united and proportional.”

Taking firmer stances defied the approach that many European leaders have offered since Trump returned to office. It had mostly entailed saying nice things about the president to try to stay in his good graces, while working furiously through other avenues to find compromise.

Trump says the U.S. needs Greenland to deter possible threats from China and Russia. But his continued insistence in recent weeks that anything short of the U.S. owning Greenland is unacceptable is testing the limits of the softer strategy.

Danish Prime Minister Mette Frederiksen said “the worst may still be ahead of us.” Speaking to parliament, she said: “We have never sought conflict. We have consistently sought cooperation.”

Greenland's Prime Minister Jens-Frederik Nielsen said at a news conference in the island's capital, Nuuk, that “we need to have respect for international law and territorial integrity.” He said those principles should unite Western democratic countries, and expressed gratitude for EU allies' support.

“International law, it's not a game,” he said, adding, "We are willing to cooperate much more, but of course in mutual respect, and if we cannot see that, it will be very difficult to have a good and reliable partnership.”

Trump's threats sparked outrage and a flurry of diplomatic activity across Europe, as leaders consider possible countermeasures, including retaliatory tariffs and the unprecedented use of the EU's anti-coercion instrument.

Unofficially known as the “trade bazooka,” the instrument could sanction individuals or institutions found to be putting undue pressure on the EU. The EU has two other major economic tools it could use to pressure Washington: new tariffs or a suspension of the U.S.-EU trade deal.

Macron warned in Davos that the additional tariffs could force the EU to use its anti-coercion mechanism for the first time against the United States.

“Can you imagine that?” he said, arguing that allied countries should be focusing instead on bringing peace to Ukraine. “This is crazy.”

In general, he said, the mechanism “is a powerful instrument and we should not hesitate to deploy it in today’s tough environment.”

Canadian Prime Minister Mark Carney, whose country is a founding NATO member, warned of global fissures beyond Greenland, suggesting it was an “illusion” and “fiction” that there remains a rules-based international order.

“Let me be direct: We are in the midst of a rupture, not a transition,” Carney said during a speech in Davos.

Belgian Prime Minister Bart De Wever said at Davos that Europe cannot be a “miserable slave to Trump.”

Others encouraged NATO leaders to stand up to Trump. Speaking on the sidelines of Davos, California Gov. Gavin Newsom slammed Europe’s response to Trump's tariff threats as “pathetic” and “embarrassing,” and urged continental leaders to unite and stand up to the United States.

“It’s time to stand tall and firm, have a backbone," Newsom, a Democrat, told reporters.

In Moscow, meanwhile, Russian Foreign Minister Sergey Lavrov strongly denied any intention by Russia and China to threaten Greenland, while also describing Greenland as a “colonial gain” for Denmark.

Trump was asked Tuesday what would happen to his tariff threats related to Greenland if the Supreme Court rules against his ability to impose import tariffs as part of a case it is considering.

“Well, I'll have to use something else,” Trump said. “We have other alternatives.” He didn't respond when asked about using force.

Also on Tuesday, the British government defended its decision to hand sovereignty over the Chagos Islands to Mauritius after Trump attacked the plan, which his administration previously supported.

Trump said relinquishing the remote Indian Ocean archipelago, home to a strategically important U.S. naval and bomber base, was an act of stupidity that shows why he needs to take over Greenland.

Become a #ThisIsTucson member! Your contribution helps our team bring you stories that keep you connected to the community. Become a member today.