Boris Johnson: "I've made up my mind" on EUThis video can not be playedTo play this video you need to enable JavaScript in your browser.Boris Johnson: "I've made up my mind" on EUCloseMayor of London Boris Johnson announces that he will campaign for Britain to leave the European Union.SubsectionEU ReferendumPublished21 February 2016Shareclose panelShare pageCopy linkAbout sharingRead description