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

Earlier today Barclays said it had allocated a further £1bn to mis-selling redress, made up of £600m for PPI and £400m interest rate swap hedging products mis-sold to small businesses.

Which? said that if current pay-out at Barclays continued its funds would run out in October.

Lloyds funds are set to stretch until just March, while HSBC would last out until December.

Which? executive director Richard Lloyd said: “Some banks have been in denial about the true scale of the payment protection scandal.

“They must come clean about how many more PPI complaints they’re expecting, publish updates on the amounts that have been paid back, and claw back bonuses from executives who presided over this £13.6bn mis-selling fiasco.

“The banks should be proactively contacting their customers and making sure it is as easy as possible for those with a legitimate claim to get their money back, without any hassle.”