Transport Secretary Geoff Hoon has resigned from the cabinet and his replacement has been named as Lord Andrew Adonis.
Mr Hoon is the latest member of Gordon Brown's cabinet to resign, after John Hutton quit as Defence Secretary and James Purnell resigned as Work and Pensions minister in the past 24 hours.
The series of resignations has forced Prime Minister Gordon Brown to bring forward a planned Cabinet reshuffle.
Lord Adonis's previous role was Minister of State for Transport. Mr Hoon was appointed as Transport Secretary in October 2008.