You're booked! Now the police hand out yellow cards

The revellers then risk arrest and a fine of up to £2,500 if they ignore the warnings issued by City of London Police.

Officers hope the scheme will stop late-night alcohol-fuelled violence breaking out by removing disruptive drinkers from the areas where their excessive behaviour is likely to provoke trouble.

So far, seven of the soccer-style yellow cards have been handed out since a trial of the powers began last month, and senior officers say that they are helping to reduce anti-social behaviour.

Inspector Andrew Wilmer, who is overseeing the use of the cards, said: "We know that the majority of people are out to have a good time when socialising in the City but occasionally there are some who show signs of anti-social behaviour after a few drinks.

"This yellow card allows us to defuse a situation that may potentially escalate into a more serious violent crime, by asking someone to leave a certain area, or perhaps the whole City, for a period of time."

Pc John Jeffrey from Snow Hill police station handed out one of the cards after he arrived at a pub where a drunk was behaving aggressively.

"Normally you'd give someone a warning but then you'd get called to some other pub where they're causing a nuisance later on. With the yellow card, though, I was able to give him a 12-hour ban," he said.

Pc Jeffrey added that he had then explained his use of the card to the publican. "He was very happy with the way we dealt with it and thought this power would be good for the future," he said.

When a person is issued with the card, they are shown a yellow form headed with the words "Yellow card" and "Direction to Leave". It warns them they face arrest and a fine of up to £2,500 if they are caught back in the area.

CCTV can be used to track their compliance and as evidence in cases where an offender ignores a ban.Those wishing to appeal against a card must go to a specified police station to speak to the duty sergeant.

Police forces have been able to issue the yellow cards since August after the Violent Crime Reduction Act came into force. The power has already been deployed by other police forces.

A Home Office spokesman welcomed the City of London's decision to use the power.

He said: "The aim of the legislation is to minimise the risk of alcoholrelated crime and disorder. It is a part of the Government's aim to end the culture of binge drinking, to discourage unacceptable alcoholfuelled behaviour, and to tackle effectively such behaviour when it occurs, protecting people from the harm it causes."

One advantage of the yellow card is that it does not require officers to fill in any time-consuming paperwork and, as an on the spot measure, is far quicker to implement than alternatives such as an ASBO or a possible prosecution. Those given the card do not receive a criminal record.