Gamblers in Coventry may soon be able to able to win a million pounds on gaming machines.

Tessa Jowell, the Culture, Media and Sport Secretary, has announced that the government is to remove the £1,000 prize limit on gaming machines as part of the relaxation of gambling laws.

It could mean casinos, such as the one to be built at Coventry Arena and another at the proposed Belgrade Plaza, offering Las Vegas-style £1million jackpots.

The big money machines will be restricted to casinos. Smaller casinos will be able to have 80 to 150 of the machines, but large "resort style" casinos like the one at the Arena, part of the Sky Blues new stadium, could have up to 1,250.

The Arena casino is set to be the largest in Britain. It is being developed by Isle of Capri, a large American casino consortium, and is expected to attract 3,000 visitors a day.

Anti-gambling groups have raised concerns about relaxing the laws, saying the number of problem gamblers could double.

A spokesperson for Gamblers Anonymous UK said: "It definitely will encourage certain people to gamble who haven't gambled before.

"They are using woolly terms and saying they are using measures to protect vulnerable and young people when all they're doing is saying they will enforce the age limit and they are leaving it to the casinos to police it. Gambling doesn't have the same physical attributes as other addictions. It's a hidden addiction, so the government ignores it, but it's happy to reap the revenue."

Paul Fletcher, chief executive of Coventry Arena, said: "The new casino will create more than 1,000 jobs and will bring a massive amount of money into the local economy.

"Whenever there is something that gives pleasure it also causes problems. We selected Isle of Capri because they are foremost in the compulsive gambling issue and have set up boards on the issue in America."