Police will go undercover to catch pubs illegally serving alcohol to drunk people in a pre-World Cup blitz.

Officers will be planted in pubs to gauge the levels of drunkenness being tolerated by landlords in the weeks leading up to the tournament.

Premises found to be breaking the law in Brighton and Hove could have their licences suspended or removed.

It is part of a zero-tolerance crackdown on alcohol-fuelled crime, violence, disturbance and under-age drinking which police fear could otherwise escalate during the World Cup.

City commander Chief Superintendent Jeremy Paine said: "Our main aim is to make this a safe and trouble-free tournament.

"The majority of supporters are law-abiding and peaceful but there are a few who use events like the World Cup as an excuse to cause trouble. Nobody wants that and, on the public's behalf, we won't put up with it."

Extra officers are being drafted in during the next month to provide a high-visibility presence in the city centre. Other action will include test purchases to catch shops selling alcohol to children, issuing more on-the-spot fines to drunk people and assigning community support officers to police taxi ranks.

Chief Supt Paine said: "We want people to come into the city to watch the games and enjoy themselves.

But anyone who thinks they can come into our city and engage in mindless, alcohol-fuelled violence can think again. We will deal with you in the strongest way possible and we will pursue custodial punishments.

"Although many premises are well run, we know the industry needs to do more to crack down on those who behave irresponsibly."

Colin Millham, landlord of the King's Arms in George Street, Brighton, and former chairman of the Sussex Society of Licensed Victuallers, said: "If you abide by the law and do not serve drunk people you have nothing to worry about. We clearly have a number of premises not doing that and the public will be reassured by this.

"Since 24-hour drinking there is concern about increased late-night disturbance. Potentially that could get a lot worse in the World Cup."