European leaders, alongside NATO chief Mark Rutte, have gone to great lengths to keep Donald Trump happy. Photo: Win McNamee/Getty Images

“We are ready to defend every inch of NATO, including our own territory,” Danish Prime Minister Mette Frederiksen told reporters as she arrived at a gathering of the alliance leaders in Ankara. “One of the reasons why we built NATO many, many years ago is if anything happens to one of us then everybody should stand up for each other.”

The remarks came after Trump on Tuesday said that “Greenland … should be controlled by the United States, not by Denmark” at the outset of NATO’s annual summit in Turkey.

“I’m not happy with NATO because of what they did with Greenland,” he added Wednesday.

Trump’s effort in January to take over the island — including his refusal to rule out the use of force — and European allies sending troops to Greenland in response brought NATO to the brink of implosion.

Reviving the issue threatens to derail the sensitive meeting of 32 leaders in Turkey.

European leaders, alongside NATO chief Mark Rutte, have gone to great lengths to keep Trump happy and play down divisions as they seek to showcase unity — even as he continues to berate allies over defense spending and their reluctance to join the U.S. war in Iran.

They also highlight that Canada and European allies have dramatically increased defense spending in line with Trump’s demands in recent years, making his current complaints less relevant.

Ahead of the meeting, leaders underlined the need to try to talk through any conflict with the U.S.

“When it comes to Denmark and Greenland itself we have a good process in place,” Rutte said ahead of the three-hour leaders' meeting on Wednesday.

“Allies can solve the problems inside NATO,” said Polish President Karol Nawrocki. “I’m sure that we will solve the problems around the many international issues.”

“If you are asking, is NATO working, and if I am confident that NATO is working, I am absolutely confident,” said Estonian Prime Minister Kristen Michal.

Yet European optimism over the summit soured after Trump’s arrival and his comments on Greenland, with leaders sending a clear signal for Trump to back off.

“That type of statement, that type of claim, Norway distances itself from,” Norwegian Prime Minister Jonas Gahr Støre said.

“We support Denmark, and we support stability in the Nordics.”

“The lines in the sand are clear: Greenland belongs to the people of Greenland,” Icelandic premier Kristrún Frostadóttir told reporters.

In a sign of Europe's hardening on the issue, that warning came even from one of Washington's staunchest allies in NATO. “Greenland is an indispensable part of Denmark,” Latvian President Edgars Rinkēvičs said.