Christine Farnish, chairman of the group, called on financial services to make retail financial products available to ordinary consumers “in a way that is understandable to them”.

“It’s got to be clear, simple and accessible, not in jargon. Doing something about the way products are presented to people is very, very important.”

Farnish said research carried out by the group showed that only those with a PhD level of education were able to understand the complex terms and conditions of PPI policies.

Compensation and refunds related to mis-sold PPI have reached £9.3bn, the Financial Conduct Authority (FCA) has said.

A further £409m was paid back in February to customers who complained about the way they were sold PPI.

This is down from £439.3m in January, but up from £360.1m in December 2012.

February’s figure brings the amount paid out for mis-sold PPI since January 2011 to £9.3bn.

The figures come from 24 firms that made up 96% of complaints about the sale of PPI last year.

PPI was the most complained about financial product in the second half of 2012, attracting 2.17 million complaints – a 5% increase on the first half of 2012 – according to FCA figures.

An analysis by consumer group Which? suggests the money banks have set aside for PPI mis-selling compensation will run out by the end of the year.

Which? said if pay-outs continue at the current rate the multi-billion funds to meet claims would run out by December.

Lloyds bank – one of the biggest sellers of PPI – has already spent £5.3bn paying compensation to customers.

The final cost to the country’s banks for PPI mis-selling is likely to be about £25bn, according to reports.