The government will announced its final decision on whether to curb stakes on fixed-odds betting terminals (FOBTs) on Thursday, with the maximum bet widely expected to be cut to £2. The machines have become a focal point for campaigners’ concerns about problem gambling and the potential for racking up large losses on machines that currently allow players to bet £100 every 20 seconds.

The culture minister, Matt Hancock, is expected to announce that the campaign to reduce the stake to £2 has been successful, a year after the result of the government’s review was due to be released. The delay has only intensified the already furious debate over the amount of harm caused by FOBTs versus the potential impact of curbing them.

Bookmakers argue that a £2 stake would effectively kill off FOBTs, which provide more than half of their annual revenue – about £1.8bn a year. A £2 stake, they have said, would result in the closure of hundreds of high street bookmakers and cost up to 20,000 jobs.

In a letter to MPs this week, Betfred warned that 900 of the firm’s shops would become loss-making overnight, forcing it to axe 4,500 jobs. William Hill has said the impact on the value on the company would make it vulnerable to a bid from a foreign firm.

Anti-FOBT campaigners say predictions of doom are exaggerated and have pointed to the wider impact on the economy caused by gamblers losing large sums on the machines, which took £1,000 from a gambler on more than 233,000 occasions in a single year. Individual losses have been known to reach nearly £14,000 in a single session of play.

A spokesperson for campaign group Fairer Gambling said: “Allowing high-stakes roulette machines in such an easily accessible environment has had disastrous consequences, impacting levels of gambling-related harm and crime. Cutting the stake back to £2 would be the right decision, and that must be enacted as soon as possible.”

The debate about the future of FOBTs has opened up divisions in both the gambling industry and the Conservative party. The Association of British Bookmakers has fought a bitter lobbying battle with Bacta, the amusement arcade body and casino operators, who want to see FOBT stakes cut and could benefit if gamblers choose their products instead.

Within the government, the drive to cut FOBT stakes initially met with opposition from the Treasury, which was concerned about the impact on its tax take.