A speaking event with former British Prime Minister Liz Truss was interrupted on Tuesday (August 13) when a banner of a lettuce descended from the ceiling. <br /><br />Campaign group Led By Donkeys claimed responsibility for the stunt after sharing videos on the social media networks. <br /><br />The video shows the banner descending slowly behind Truss as she addressed audience members, revealing a large lettuce with the words "I crashed the economy".