Banning calculators from national tests in primary schools is a “backward step”, leading academics and researchers have warned.

University dons from Oxford, Cambridge and Kings College London have criticised ministers’ decision to prevent pupils from using the devices during their Sats exams.

Back in 2012, education minister Elizabeth Truss announced that calculators would be banned from this year, stating that all pupils should know their times-tables, and be able to add, subtract and divide before they begin using calculators.

Hundreds of thousands of 11-year-olds across England are sitting Sats papers in English and maths this week.

As the tests took place, a number of academics and researchers from leading universities suggested that there was a lack of evidence to support banning primary school children from using calculators.

The move comes as Singapore, one of the countries that regularly comes among the top performing nations in international league tables, has announced it intends to reintroduce calculators to older primary school pupils.

Jeremy Hodgen, professor of maths education at Kings College London, said countries that ban calculators “tend to perform worse than others”.

“As a result, Singapore has recently re-introduced calculators in upper primary schools,” Prof Hodgen said. “Many children not only find formal procedures like long division and long multiplication confusing but also that they rarely use the methods taught in school to solve problems.”

Ken Ruthven, professor of education at Cambridge University, said the arguments put forward for the change were “not convincing”.

“As well as making calculation more efficient and reliable, calculators allow people to tackle mathematical problems in new ways,” he said.

“Making intelligent use of tools such as these underpins a great deal of the mathematics that is done in our contemporary world.”

Terezinha Nunes, professor of educational studies at Oxford University, added: “Removing national tests where pupils can use calculators will place greater emphasis on the testing of calculation skills and less on the assessment of mathematical reasoning. I think one can safely say that is a step backwards.”

When it announced its decision two years ago, the Department for Education said research published in 2007 had shown that around 98 per cent of 10-year-olds in England were allowed to use calculators in maths lessons, compared to an international average of 46 per cent.