Nigel Farage said he doesn't think Donald Trump will invade Greenland as that "would be the end of NATO".
The Reform UK leader stressed he hadn't spoken with the US president about this issue but he doesn't think he will follow through on his threats.
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President Trump has been vocal about his desire to annex the self-governing island, despite it being part of Denmark - a NATO ally.
The White House has said the "US military is always an option" in taking over Greenland, which it wants because of its strategic Arctic location and mineral resources.
At a press conference in London, Mr Farage said the president has "been rather busy" and he hasn't spoken with him.
But he added: "Ever since 2016, the narrative has been that Trump wants to destroy NATO, but actually, whenever I talked to Trump in 2016 about NATO, he's always said, no, that's not right. I want to strengthen NATO."
He pointed to the fact President Trump's interventions have led to an increase in promised defence spending across Europe.
He said: "In many ways, he has strengthened NATO. However, if he were to do this using military force, that probably would be the end of NATO which is why he won't do it, in my opinion."
He added: "Would I stand up to him now? The great thing of being friends with people is friends don't always agree with everything that the other one says."
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In recent days, Danish Prime Minister Mette Frederiksen has warned that US military action to seize the territory would spell the end of NATO.
And in a joint statement on Tuesday, European leaders including Sir Keir Starmer and Emmanuel Macron said they will "not stop defending" Greenland's territorial integrity.
But a later statement from the White House showed no sign of toning down the rhetoric - and defended potentially taking a military approach, insisting it is "always an option" open to the president.
"President Trump has made it well known that acquiring Greenland is a national security priority of the United States, and it's vital to deter our adversaries in the Arctic region," it said.
"The president and his team are discussing a range of options to pursue this important foreign policy goal, and of course, utilising the US military is always an option at the commander-in-chief's disposal."
(c) Sky News 2026: Farage warns Trump invading Greenland 'would be the end of NATO'

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