Tesco has reported strong sales growth in its first quarter bolstered by online as lockdown measures prompted a surge in demand.

Tesco reported an 8% increase in UK and Republic of Ireland like-for-like sales to £12.2bn in the 13 weeks to May 30, up 8% to £13.4bn across the group overall.

Sales in the UK were up 9% in total, driven by a 49% leap in online sales during the period and up 90% at peak in May. 

In response to the coronavirus pandemic Tesco invested in doubling the capacity of its online delivery service over a five-week period during the crisis, with 600,000 delivery slots more than doubling to 1.3 million.

Tesco ploughed £4m into this initiative, which it said was partially offset by the business rates relief it had received during the pandemic.

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Although the frequency of shopping during the period was down 32% in the UK during the period the average basket size jumped 64% as shoppers stocked up on essentials.

Convenience sales also reported a 10% uplift during Tesco’s first quarter.

Chief executive Dave Lewis said: “Through a very challenging period for everyone, Tesco colleagues have gone above and beyond, and I’m extremely proud of what they’ve achieved.  Their selfless efforts, combined with our embedded strategic advantages in stores and online, have helped to ensure that everyone can get the food they need in a safe environment.

“In just five weeks, we doubled our online capacity to help support our most vulnerable customers and transformed our stores with extensive social distancing measures so that everyone who was able to shop in store could do so safely. 

“The costs of doing this have been significant and only partly offset by business rates relief and increased volume. We see the balance as an investment in supporting our customers at a time when they need it most.”