Coun Kennedy said that when he was first elected 18 years ago ‘politics tended to be more civilised’.

“I have never once spoken to Coun Bennett since I returned to the council a few months ago. This has not been a great introduction from the young man.

“I trust that one of the senior members of the Tory group will have a word and tell him to grow up.”

Coun Kennedy said that he is concerned that Amey, which last year won the £2.7 billion 25-year contract to maintain Birmingham’s roads, would not send staff to evening ward committee meetings.

He added: “We cannot give up the streets to criminals or fear. As councillors we have encountered these problems and worked around them.”

In the email he explained: “We cannot allow ourselves to be cowed by any incident however serious, there can be no compromise in carrying out public duties and there can be no ‘no-go’ areas.”

Amey said that their staff would not attend the evening meetings unless specifically requested, and then they would not travel alone.

A member of staff had been attacked last year after leaving a meeting the company explained.

Conservative group deputy leader Robert Alden described the row as an over-reaction as the company had pledged to cover essential meeting and it was a waste of resources sending staff to non-essential meetings.

“We should try to work with our staff rather than insult them for not wanting to walk alone in the dark.”