A court in central China has told judges they cannot wear heavy make-up, get a tattoo or 'frolic' with colleagues while on duty in a list of 55 new regulations aimed at improving etiquette.

A notice issued by the high court of Henan, the top judicial authority in the central province, also banned judges from using certain phrases in the courtroom, including 'Are you the judge or am I?' and 'You will certainly lose this case'.

Judges would also not be allowed to wear jewels; hold hands with colleagues; dye their hair; wear tattoos or painted nails; or grow long hair, beards or shave their heads, according to a report in the Beijing Times.

To ensure judges treated their office with respect - and not taint it by questioning lawyers' abilities or calling trial witnesses 'annoying' - plainclothes inspectors would be posted to monitor court proceedings, the paper said.

Judges who broke the rules would receive 'criticism and education' and serial offenders would be fired, it said.

Authorities in China have also asked police and taxi drivers to mind their manners.

In September, Beijing said it would crack down on police officers smoking, eating and chatting on duty, while female taxi drivers in April were ordered to leave their scarves and chunky earrings at home.