In the 1955 general election, Cunningham was chosen as the new Ulster Unionist MP for South Antrim. He was a delegate to the Council of Europe and Western European Union Parliamentary Assembly from 1956 to 1959.
Cunningham's selection as the new Ulster Unionist MP for South Antrim in the 1955 general election marked a significant development. His subsequent role as a delegate to the Council of Europe and Western European Union Parliamentary Assembly from 1956 to 1959 highlighted his involvement in international affairs.