In 1989 he was minister of education and sciences and he was minister of farming, nature management and fishery in 1989–1990. He was a member of the Senate of the Netherlands from 11 June 1991 until 10 June 2003. And as such he was parliamentary group leader in the senate from 18 June 1999 until 2 October 2001 when he became president of the Senate until 2003.