Robert Edward Diamond Jr. is an American banker and former chief executive officer of Barclays plc. In 2010, he became its president and deputy group chief executive; and in January 2011, succeeded John Varley as group chief executive of Barclays. Diamond resigned as chief executive of Barclays after a Bank of England hearing on July 3, 2012, following controversy over manipulation of Libor interest rates by traders employed by the bank.