Lib Dem Cllr Eleanor Scott refused to chair a public meeting as the cabinet member for the environment because Mark Austin was lined up to make deputations.

She was offered security guards to sit in on the meeting – but called it off on the morning it was due to take place.

It meant two items on the agenda – the council's noise enforcement policy and an update on air quality – had to be put back by four days to a cabinet meeting.

Mr Austin, 51, of Francis Avenue, Southsea, first started tackling Portsmouth City Council around three years ago over the Northern Quarter development.

Now he regularly appears at council meetings to speak on a range of subjects.

He has also been to councillors' homes and writes about them on a website.

His actions have caused a handful of Lib Dems to make moves to silence him.

Cllr David Stephen-Butler has reported him to the police for harassment.

At a meeting of the full council last week, Cllrs John Ireland, Cheryl Buggy and Stephen-Butler, along with fellow Lib Dems Jacqui Hancock and Margaret Foster, walked out when Mr Austin appeared to speak.

Mr Austin said: 'I have never been threatening or violent towards anyone.

'I am exercising my democratic right to test and question the council and the decision to cancel the meeting shows utter contempt for the council's own constitution and the law.

'This shows we have not got Liberal democracy in Portsmouth if they are trying to ban a member of public from holding the council to account.'

Cllr Scott said she had cancelled the meeting because she did not feel safe knowing that Mr Austin planned to attend.

She said: 'Obviously the risk was deemed enough to warrant security guards so I took a stand and said I would not chair a meeting where there would be that risk.'

>> Vote in our latest web poll.