Tesco is to give instant rewards to customers if their baskets are more expensive than its big four rivals, under a new scheme expected to launch on Monday.

The revamp of its Price Promise scheme, understood to be under the new name Brand Guarantee, follows trials in Northern Ireland of the new system, revealed by The Grocer earlier this week.

When asked by The Grocer on Monday whether it planned to roll the scheme out across the UK, following the same path it used with Price Promise, the retailer refused to elaborate but today a spokeswoman admitted next week would see the new scheme used to step up the price war against its rivals.

It is thought the rewards will be based only on the comparative price of branded products, unlike Price Promise which includes own label and brands.

The scheme will be rolled out across Tesco’s estate except for its Tesco Express line up.

Tesco’s Price Promise scheme, which was also piloted in Northern Ireland prior to a wider roll out in March 2013.

“We’re always looking at ways to make the shopping trip that little bit easier for customers, including improvements in customer service, updating our product ranges and continuing to offer everyday low prices on the products that matter most. We’re looking forward to unveiling the next steps in this programme to customers next week,” said a Tesco spokeswoman.

The move comes in the same week that rival Morrisons confirmed it was abandoning its Match & More price match scheme to create a simpler loyalty programme. Customers will now get five points for every £1 they spend in store. Once they reach 5,000 points they will receive a £5 voucher.