Guildford BC leader Stephen Mansbridge has quit as a councillor, saying he cannot accept changes to the way the council is run.
Mr Mansbridge had voted against the introduction of new executive advisory boards.
In a statement, he said: ‘I have been minded to step down for some time and while I have been asked to stay I no longer feel able to do so.
‘I hold strong views about how the council is run and about its ability to make strong and good decisions.
‘I cannot accept the changes in governance, which is why I voted against them at a recent council meeting.
‘I have been passively in favour of a petition for a directly-elected mayor because a successful petition would nullify any petition that attempts to weaken the council's governance under the shroud of improved democracy.
‘My view has evolved, in line with George Osborne's direction for greater devolution, to be that we need larger entities with directly elected mayors.'?
Deputy leader Cllr Nigel Manning will take over the role of leader until a new one is elected on 8 December.
Cllr Manning said: ‘There is a lot to do and we continue to work on the challenging programme we've agreed.'