In a referendum held on 23 June 2016, Britain voted to withdraw from the European Union, with a result of 52% for withdrawal and 48% for remaining within the union. David Cameron, who as Prime Minister had campaigned to remain within the European Union, announced on 24 June 2016, immediately following the announcement of the referendum results, that he would resign from his post. Following the first stages of a Conservative Party leadership election, Home Secretary Theresa May's only remaining competitor, Andrea Leadsom, withdrew from the race on 11 July 2016. Following this announcement, Cameron said that he would step down from his post on 13 July. Cameron formally tendered his resignation to Queen Elizabeth II on that day, who subsequently appointed Theresa May as his successor.