Your pizza may be delivered to you within 30 minutes or your money back, but it may also be delivered by workers who are living in cramped conditions and who earn next to nothing because they are loaded with debt by their employer.

Such are the allegations against branches of the biggest global pizza chain by Britain’s biggest union. Domino’s Pizza is poised to become the latest cause célèbre in the union’s fight for the better treatment of migrant workers after Unite yesterday staged a demonstration against the sacking of Hungarian workers at three pizza branches in Derby.

The demonstration comes as unions are increasingly highlighting the plight of migrant workers who can fall victim to unscrupulous employment agencies and fail to understand their employment rights as they struggle with language difficulties.

The union said that matters at Domino’s came to a head when workers challenged deductions from their pay which would leave them with a pittance at the end of the week or in hock to the company because of loans for cars and car insurance. The three Domino’s franchises, which are among 26 owned by the millionaire Surinder Kandola, require pizza delivery workers to be owner drivers with their own motor insurance.

Unite plans to take the cases of 12 Hungarian workers at Domino’s to an employment tribunal, claiming that deductions were made illegally. Some weekly pay slips for workers show workers owing the company more than £137 or receiving net pay of as little as £8. Simon Wallace, Unite’s Derby officer, said: “Domino’s is a global brand. It should be setting a lead in employment practice, not shielding those making vast profits by exploiting vulnerable workers.”

Mr Kandola said he would fight the employment tribunal actions, although he said that the workers’ pay slips “could have been clearer”. But he said that “there is a full audit trail of the deductions, which has been given to Domino’s”.

He said that delivery workers were required to have their own cars because that was the business model that worked for the franchises. He said mopeds were not safe.

Mr Kandola’s franchises offer accommodation to migrant workers in 26 houses, one for each franchise, at £50 a week. He says that the accommodation is good. The workers say that it is cramped and without proper beds. Derby City Council has said that it is concerned at the accommodation.

Domino’s said the matter was being investigated and that it sought to ensure good standards at all its franchises. In the past 18 months it has removed franchises from 32 of its 400-strong chain. Unite says it has received similar complaints from workers at other divisions of Domino’s. But the company says it has not yet seen any evidence of this.“We are looking at this from every angle but there is nothing to suggest that there are wider problems,” said a spokesman.

Unions are putting greater efforts into working with migrant workers because they say they suffer greater exploitation than British workers who do not have language difficulties and know where to seek help. The GMB forged links with Poland’s union, Solidarity, so it could more easily recruit and assist Polish workers in Britain.

Last year the T&G, which merged with Amicus to form Unite, mounted a campaign to increase the pay of cleaners in the City of London, many of whom are foreign nationals, by “naming and shaming” the ultimate employers of the cleaners – investment banks and large financial institutions. This is increasingly becoming part of the unions’ campaigning strategy as they shift away from straightforward strike action, which hits poorly paid people hard anyway.

Claims against Domino’s Pizza will be lodged by the Hungarian workers at Derby’s employment tribunal services on Monday and are expected to be heard next month.

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