Asda has dropped the £15 cap introduced in October to its Asda Price Guarantee vouchers.

The retailer imposed the limit after hundreds of shoppers exploited a loophole in its APG website to redeem vouchers totalling thousands of pounds.

But three members of the public complained to the Advertising Standards Authority that Asda would not be able to honour the “10% cheaper or we’ll give you the difference. Guaranteed” promise in its ads.

Asda could no longer ‘guarantee’ to be 10% cheaper than rivals when a maximum of £15 could be redeemed from any one shop - meaning Asda could only ‘guarantee’ to be £15 cheaper than its rivals, not 10%, they argued.

However, the case was dropped after Asda suggested it remove the cap instead of the word ‘guarantee’. The ASA said it hadn’t issued Asda with an ultimatum, but that dropping the cap had resolved the issue.

“We didn’t direct Asda to remove the cap but that solution, proposed by them, satisfied us that the issue has been resolved without the need for formal action,” said a spokesman.

Asda claimed it had fixed its website and no longer required a cap anway. “We introduced a cap after we found a glitch. The glitch has been fixed and the cap has been removed,” said a spokeswoman.

However, as a safeguard, Asda has introduced small print that states if a voucher is generated for over £15, Asda will withold the voucher for seven days in order to check it has been “accurately calculated”.