A private security firm will once again marshal Liverpool city centre taxi ranks to try to reduce violence in the run-up to Christmas.

Officials said frustrations could often overspill into fighting as people wait in long queues for a cab home.

A team of security staff, backed by Merseyside Police, will patrol ranks in Victoria Street, Copperas Hill and by the Chinese Arch every weekend.

Last year, the scheme resulted in a 36% drop in violence from 2006.

Peter Jones, of the Liverpool Chamber of Commerce, said: "There were worries about using a private security company on the city centre streets late at night, but the staff involved have been extremely professional and have been accepted by everyone as a tremendous calming influence."

The scheme is being run by the Liverpool Citysafe partnership, which is made up of Merseyside Police, the council and Liverpool Chamber of Commerce.

Security will patrol the ranks every Friday and Saturday night from now on until 0400 GMT, as well as Christmas and New Year's Eve.