The European Union is ready to strike back at Donald Trump over his tariff threats as he seeks to take Greenland, European Commission President Ursula von der Leyen said, toughening her rhetoric against the US president.

The EU chief offered to deepen cooperation with the US in Arctic region and termed imposing additional tariffs a "mistake."

The European Union is preparing a response to U.S. President Donald Trump's threat to impose tariffs on NATO allies over Greenland, with leaders set to discuss retaliation options at a summit on Jan.

U.S. President Donald Trump’s threats to annex Greenland and impose tariffs on its backers pose a challenge to Europe’s security, principles and prosperity, European Council President António Costa said on Wednesday.

President Donald Trump threatened Saturday to impose new 10% tariffs on imports from several European countries. It could unravel months of progress made during trade negotiations settled after Trump’s trade war last year.

President Donald Trump has posted private text messages from the head of NATO and France's president to the U.S. President, shortly after Norway's leader confirmed a leaked exchange did show tense correspondence between the Republican and NATO leaders.

BRUSSELS (AP) — U.S. President Donald Trump’s threats to annex Greenland and slap tariffs on its backers pose a challenge to Europe’s security, principles and prosperity, a top EU official said on Wednesday.