There are two such offices - Crown Steward and Bailiff of the Chiltern Hundreds and of the Manor of Northstead.

BBC: Chris Huhne officially no longer an MP

Others who have resigned as an MP by being appointed to the Chiltern Hundreds include Roy Jenkins, Brian Walden, Neil Kinnock, Tony Blair, David Davis, and Eric Illsley.

BBC: Chris Huhne officially no longer an MP

The move is a formality and either it or a similar title - the office of the Crown Steward and Bailiff of the Chiltern Hundreds - is conferred on resigning MPs, whether or not they accept it.

BBC: Martin McGuinness