Watch: Why is there a 'black cloud' over unity at the Nato summit?

Watch: Why is there a 'black cloud' over unity at the Nato summit?To play this video you need to enable JavaScript in your browser.This video can not be playedWatch: Why is there a 'black cloud' over unity at the Nato summit?CloseUS President Donald Trump is in Turkey attending a Nato summit following a ramp up in tensions between the US and Iran. The latest trading of strikes were not the only topic of discussion at the summit, defence spending and Trump's reiteration of his interest in purchasing Greenland were also brought up. The BBC's Frank Gardner explains how the latest developments have cast a "black cloud" over discussions of unity at the summit.More on this story. SubsectionWorldPublished37 minutes agoShareclose panelShare pageCopy linkAbout sharingRelated topicsNatoFollow Natoclose panelYou are now following NatoUpdates from your News topics will appear in My News and in a collection on the News homepage.Donald TrumpFollow Donald Trumpclose panelYou are now following Donald TrumpUpdates from your News topics will appear in My News and in a collection on the News homepage.Middle EastFollow Middle Eastclose panelYou are now following Middle EastUpdates from your News topics will appear in My News and in a collection on the News homepage.United StatesFollow United Statesclose panelYou are now following United StatesUpdates from your News topics will appear in My News and in a collection on the News homepage.Read description