A cross-party group of protesters gathered in Thorpe Hamlet this morning to demand the resignation of a defected councillor.

They called for Cllr Phil Hardy, who was elected as a Green Party councillor but switched to the Conservatives in December, to stand down and face a by-election.

The event was organised by residents in the ward, who say they represent the 80 per cent that did not vote Conservative in 2009 and accuse Cllr Hardy, who was last week appointed the green adviser to Norfolk County Council cabinet, of betraying the policies upon which he was elected.

The demonstration was attended by the leaders of the Green and Liberal Democrat groups on Norwich City Council, and prospective Labour parliamentary candidate Clive Lewis.

Mr Lewis said the issue was 'beyond party politics'.

'It's a matter of principle. What he has done is morally questionable, and if he is a true democrat he should resign and stand for re-election as a Tory.

'He is under the delusion that people voted for him personally – that's not the case. He was elected on a platform, and that platform is now different.'

Cllr Lesley Grahame, Green Party city councillor for Thorpe Hamlet, said: 'Philip Hardy should stand down as he has betrayed the principles and policies upon which he was elected and the people who voted for him.'

Thorpe Hamlet resident Holly Sandiford, who organised the event, said: 'I think he let us all down – it's morally wrong. It worries me that someone like him is in a position of power. I've spoken to so many people who are so angry at what he has done.'

City council Green leader Claire Stephenson has written to other party leaders, calling on them to agree a unified policy for defectors, requiring them to stand for re-election for their new party.