A founder member of the Democratic Unionist Party (DUP) and Deputy Leader from 1980, he served as a member of the UK parliament (1979–85, 1986–2010) and became known as an uncompromising Unionist. In 1999, although he had strongly opposed the Good Friday Agreement (see northern ireland), he became a member of the new Northern Ireland Executive. In 2008 he succeeded Ian Paisley as Leader of the DUP and as First Minister, working effectively with Martin McGuinness of Sinn Fein as Deputy First Minister. He stepped down temporarily in 2010 following corruption allegations, resuming his role three weeks later. In November 2015 he resigned as leader of the party and was replaced by Arlene Foster.