President again disparages allies and tells Fox News he is ‘not sure’ Nato would come to US’s defence

Donald Trump has again disparaged America’s Nato allies, claiming that troops from allied nations “stayed a little back, a little off the frontlines” while fighting in Afghanistan in support of the US campaign against the Taliban.

The only time Nato has ever invoked its mutual defence clause – stating that an attack on one member represents an attack on all – came after the terrorist attacks of September 11, when member states deployed thousands of troops to Afghanistan.

More than a thousand non-US service members were killed in the conflict, and Trump’s comments are likely to further heighten tensions between the US and its allies.

As he ratchets up his grievances against Nato, of which the US is a founding member, Trump has repeatedly questioned whether the 31 other nations that make up the alliance would come to the US’s defence.