A council is being investigated by the Information Commissioner's Office after it monitored a member's mobile phone calls.

Officials at Liverpool City Council trawled through the phone logs and emails of Labour councillor Joe Anderson in an internal probe.

The inquiry was attempting to discover who leaked information to a journalist about a £2million increase in the cost of staging a Sir Paul McCartney concert in the city.

'Appalling': Councillor Joe Anderson, Labour opposition leader on Liverpool City Council, has demanded disciplinary action for the person who authorised a search of his mobile phone records

Under town hall rules, officials are banned from looking at councillors' mobile phone records.

The council has apologised to Mr Anderson, who is the leader of the Labour opposition, and reported the matter to the Information Commissioner's Office.

Last night, Mr Anderson said: 'This was an appalling breach of the rules.

'I want the person who authorised it disciplined.'

Mr Anderson was one of several people subject to the inquiry.

The Information Commissioner's Office - which protects personal information - confirmed it was investigating a possible breach of the Data Protection Act.

Liverpool City Council said: 'We have taken steps to ensure this cannot happen again.'

The scandal is the latest by snooping councils.

In April, it was revealed that Poole Borough Council in Dorset spied on a family to check they lived in the right school catchment area.

Other councils have admitted using laws intended to thwart terrorists to probe petty offences such as littering and poor parking.