He increased his majority in 1970 despite a strong challenge by future Plaid Cymru leader Dafydd Wigley.
He became a front-bench spokesman on Welsh affairs, in a team headed by George Thomas, but was sacked in 1972 over his support for entry into the European Economic Community.
He was then appointed to lead Labour's campaign in Wales for a "yes" vote in the referendum to remain in the EEC.
In 1981, he was selected to fight Ynys Môn, but withdrew in March 1983, shortly before the 1983 general election, in protest at Labour's policies of withdrawal from the EEC, unilateral nuclear disarmament, and closure of US military bases in the UK.
He was a member of the Historic Buildings Council for Wales from 1971 to 1976, and began to edit The Solicitor's Diary for Waterlow's in 1973.