Trump has frequently railed against NATO and its members, accusing them of not spending enough on defense and relying on the United States to protect Europe.

At the Ankara summit, NATO members are expected to address questions over defense spending and the U.S.’s evolving role in the alliance.

US President Donald Trump expects all Nato allies attending next week's summit in Ankara to be on a path toward spending 5 per cent of Gross Domestic Product (GDP) on defence and…