As President Trump looks to fix the issues that irk him the most, the issue of NATO defense spending — one of his perennial bugbears — is returning to the fore.

Europe’s military heavyweights have already said that meeting President Donald Trump’s potential challenge to spend up to 5% of their economic output on security would be challenging

Europe should welcome rather than rebuff U.S. President Donald Trump's call for other NATO members to ramp up their military spending, Polish Prime Minister Donald Tusk said on Wednesday, stressing the importance of security to the continent.

Congress passed legislation that a president cannot unilaterally withdraw from NATO, setting up a major legal fight if Trump tries to pull the US out.

Anders Vistisen, a Danish member of the European Parliament, has told U.S. President Donald Trump to "f*** off" after Trump again expressed interest in purchasing the island of Greenland. Newsweek has contacted the White House and Vistisen for comment via email.

Russia on Thursday rejected the idea of NATO countries sending peacekeeping troops to Ukraine in the event of a ceasefire in the war with Russia, saying such a move would threaten to cause an "uncontrollable escalation".

New US president is serious about tariffs and angry with the EU. Keir Starmer must use UK's freedoms outside the bloc to escape trade wars and thrive

Transatlantic military alliance chief echoes Ukrainian leader Volodymyr Zelenskyy in stinging remarks at the World Economic Forum.

Committing 5% of GDP to defense is a fine idea, for the U.S. too.

NATO chief Mark Rutte supported Trump's push for higher defence budgets and warned that a Russian victory in Ukraine would damage NATO's credibility and increase costs.