Tesco boss Dave Lewis has hailed early trading at its two Jack’s discount stores – and hit back at suggestions the format could confuse shoppers.

Lewis said he was “very happy so far” with the performance of the shops in Chatteris, in Cambridgeshire, and Immingham, Lincolnshire, both of which opened last month.

Two more are set to launch tomorrow in Edge Hill and St Helens as Tesco pushes towards its initial target of opening 10 to 15 Jack’s shops.

“It’s two stores, but we’re really very happy so far,” Lewis said as Tesco unveiled a 2% increase in statutory pre-tax profit to £564m in the first half of its financial year.

“The two stores are trading very well, customer feedback is really very good. So far, so good; but it’s two stores.”

Lewis hailed Jack’s price position against the market and insisted both stores had “attained” the position as being “the cheapest in town”.

He vehemently dismissed suggestions that the rollout of the Jack’s format could confuse Tesco shoppers.

It came as photographs emerged on social media of Tesco-branded products apparently being sold in Jack’s – at a lower price than customers would pay in Tesco.

But Lewis said: “I’m not sure customers are confused. As we do when we launch any score, we track what customer reaction to it is. The net promoter score and the feedback we are getting from the two stores is really very strong.

“I saw something on Twitter last night that we looked at – we’ve investigated. It appears to be completely rogue.

“I’ve checked with the team, there is, and there will be, no Tesco product in a Jack’s store.”

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