NATO Secretary-General Mark Rutte is working to keep the alliance united and Donald Trump engaged. But disputes over burden sharing, US military commitments, and the Iran war are creating a major test for NATO unity.

President Trump has berated and belittled many of his European counterparts expected to attend next week's NATO summit in Turkey. But host Recep Tayyip Erdogan has drawn on his close ties with th

Officials say that, to appease the US, ‘burden-shifting’ rather than simply ‘burden-sharing’ will be one of the main themes in Ankara as the EU and others face pressure to ramp up their own production of defence and security equipment.