Two-fifths of adults fail to understand their finances, with Britain lagging behind Germany, Australia, Canada and the US, Rishi Sunak has warned.  

The former prime minister told the Daily Mail that Britain is stuck in a culture of believing 'some people just aren't maths people', which is affecting everything from managing debts to saving for retirement. 

He and his wife, Akshata Murty, set up a numeracy charity in March to help implement financial literacy into the school curriculum. 

Research from the Richmond Project - named after Mr Sunak's North Yorkshire constituency - has today revealed that 40 per cent of Britons lack the skills to manage their money. And women in particular are being left behind. 

The study, involving more than 10,000 adults, tested their understanding of several key concepts: compound interest, inflation and risk diversification. 

These are the global benchmark for evaluating basic financial knowledge, yet only 28 per cent of Britons demonstrated that they had a grasp on all three. 

It means that millions taking out mortgages, loans and credit cards are unable to understand how the interest works.

The UK trails behind Germany (53 per cent), Switzerland (50 per cent), the Netherlands (45 per cent), Australia and Canada (43 per cent) and the US (30 per cent).

Men were shown to be more confident across every age group, with the gap widening sharply around middle age, when financial decisions can be most crucial, with mortgages, pensions, childcare costs and career breaks.

Ms Murty has previously spoken about 'maths anxiety' - the fear around numbers that mothers often suffer from and pass down to their daughters.

Mr Sunak said: 'Even for us - a couple who are on the more confident end - we had to think about it with the kids.

'We incorporated maths into our day-to-day lives as they were growing up, through things as simple as counting the stairs as we walked up and down them, to naming shapes with a pizza - triangular slice, square box, circular pizza - it all helps.' 

Ms Murty has also released children's books to help 'get kids excited about numbers through stories', which have been sent to more than 300 schools.

Starting early, the charity says, can help build long-term financial resilience, but Britain needs a 'cultural shift' to get there.

'Financial literacy underpins so many things - what job you apply for, what opportunities you pursue and building security for you and your family,' Mr Sunak said.

'If you can help people improve their confidence with numbers, you're giving them the best possible chance to live a more fulfilling life.'

Financial education will become compulsory for all pupils in England from September 2028, following a Government review.

The Richmond Project is helping to develop the new curriculum alongside the Department for Education, which will involve lessons on budgeting, compound interest, money management and mortgages.

It is also supporting initiatives to help parents with their own financial literacy.