Guthrie initially supported the continuance of the United Kingdom's presence in the European Union in the 2016 referendum on Britain's membership of the European Union, but suddenly switched to an advocacy of withdrawing from it less than a week before the vote was held, issuing a public warning of the ambitions inherent in the E.U. for the creation of a new "European Army", which he stated "would be a disaster". He is on the advisory board of Veterans for Britain an organization with the stated aim of supporting " Her Majesty's Government in the task of restoring full sovereign control to all aspects of the defence of the Realm " following the EU referendum.