Polish Prime Minister Donald Tusk issued a dire warning about the future of Europe, saying the continent is “finished” without unity, following a week that saw fractures in the stances of EU countries on foreign policy. 

Tusk, a pro-European centrist, wrote on social media Monday that Europe won’t be taken “seriously” if it is “weak and divided: neither enemy nor ally.”  

“It is already clear now. We must finally believe in our own strength, we must continue to arm ourselves, we must stay united like never before,” he said. “One for all, and all for one. Otherwise, we are finished.” 

Tusk’s warning came after U.S. President Donald Trump revived his threats to take control of Greenland, the self-ruling Danish territory that he has long coveted. “We need Greenland from a national security situation,” the American leader told reporters on Air Force One on Sunday. 

“We will deal with Greenland in about two months. Let’s talk about Greenland in 20 days,” he added, without giving more information about what he meant.  

Those remarks came after the U.S. launched strikes on Venezuela and arrested its leader, Nicolás Maduro, in an audacious nighttime raid. The dramatic operation raised fears in Europe that Washington could attempt a takeover of Greenland, prompting Danish Prime Minister Mette Frederiksen to issue a stern rebuke.  

Annexing the Arctic island would make “absolutely no sense,” she said Sunday, with fellow Nordic nations Norway, Finland and Sweden expressing their support. 

The EU’s response to the U.S. intervention in Venezuela has been somewhat varied. High Representative Kaja Kallas called for “restraint” in a statement that garnered the support of 26 member countries, minus Hungary. 

Spain, meanwhile, split from the EU and joined five Latin American countries in a far more forceful statement slamming Washington’s attack on Venezuela’s sovereignty and calling for the nation’s natural resources not to be exploited, amid Trump’s pledge to take over its oil fields.  

While most EU member countries have issued their own cautiously worded statements urging respect for international law, Italy struck a more approving note, calling military action “legitimate against hybrid security attacks.”

But Slovak Prime Minister Robert Fico was scathing, saying the U.S. incursion in Venezuela was “further evidence of the breakdown of the world order,” and in a Facebook post on Monday, Hungarian Prime Minister Viktor Orbán said the “liberal world order is in disintegration.”