 The Wilson administration had merged the Colonial Office and the Commonwealth Relations Office in 1966 into the Commonwealth Office , which , two years later , was merged with the Foreign Office , to form the Foreign and Commonwealth Office ( FCO ) . Heath appointed Douglas @-@ Home to head the department , with , once again , a second cabinet minister , this time Anthony Barber , principally responsible , as Heath had been in the 1960s , for negotiations on Britain 's joining the EEC . This time , however , both ministers were in the Commons ; Barber 's cabinet post was officially Chancellor of the Duchy of Lancaster . 
