Secretary of State for Work and Pensions Iain Duncan Smith is looking into complaints by MPs that dozens of Jews have been forced to seek work on Saturdays or face losing their job seekers allowance.

The move has come in response to concerns expressed by Labour MPs Ivan Lewis and Hazel Blears.

Mr Duncan Smith told Mrs Blears that the religiously observant should not be forced to work on “sacred days”.

In a letter, he wrote: “A person who follows a particular religion may object to taking employment which requires them to work on a day which is considered sacred.”

Mrs Blears, along with fellow MP Graham Stringer, has taken up the case of a Salford woman who has been denied JSA since objecting to working on the festival of Shavuot in May.

The woman, who did not wished to be named, said she had had to take a loan to buy food. “It’s a very cruel way to behave to a person who’s been trying to find work,” she said.

The denial of JSA to observant Jews in the Manchester area came to light when Jacob Slinger won a landmark tribunal appeal over his treatment by a job centre, which was ordered to pay over £1,500 in denied benefits.

But in a recent letter to Mr Slinger, DWP’s work services director Neil Couling said that his claim of religious discrimination was “nonsense”.

Mr Couling wrote that the decision to refuse JSA was not based on religion but on Mr Slinger’s refusal to work certain hours on Saturdays which “did not give you reasonable prospects of securing employment”.