Why Donald Trump says the Iran ceasefire is over

The US and Iran are trading strikes again as Donald Trump turns to his weapon of choice - sitting down at press conferences and calling people names. America’s insulter-in-chief has used a NATO summit to say Iran are “sick people" and "scum" and that the ceasefire is now "over”. It was a fragile agreement that has broken down after tankers were targeted in the Strait of Hormuz - so who is to blame for the latest violence? What next for the ceasefire and could we soon see a return to all-out war? Niall is joined by Sky’s military analyst Michael Clarke.