 Throughout Clark's time in Parliament, the Ulster Unionists received the Conservative whip, though retaining an independent identity and Council, and Clark sat on the Government, and later Opposition, benches with Conservative MPs from Great Britain.Clark chaired the Conservative MPs' East Africa Committee in 1963-65 and was a part of the British Parliamentary delegation to the Council of Europe and the Western European Union from 1962 to 1965.Clark's background in the Colonial Service and his abiding interest in East Africa led to his appointment as an electoral observer.