Tesco has recorded a strong uplift in sales over the festive period as boss Ken Murphy says the grocer “delivered a record Christmas across all of our formats and channels”.

The supermarket giant recorded an 8.4% rise in total sales across the UK and Ireland in the 6 weeks to January 9, up 6.3% on a like-for-like basis.

This uplift followed a strong third-quarter performance by the grocer, which saw sales up 8.5% and 6.2% in total and like-for-like terms respectively in the 13 weeks to November 28, resulting in sales of £18.2bn over the 19-week period.

Tesco’s festive performance was bolstered by online demand. Online sales were up over 80% during its third quarter and Christmas trading period, equating to an additional £1bn of revenue, and Murphy said Tesco “delivered over 7 million orders containing more than 400 million individual items over the Christmas period”.

Tesco’s sales grew across all formats, categories and channels during the period as UK shoppers treated themselves to more upmarket and diverse festive fare. The supermarket chain’s Finest product range recorded a 14% rise in sales over the Christmas period, while sales of plant-based products rose more than 90%. The supermarket’s general merchandise division posted a 4% rise in sales driven by strong performance in toys, home and electricals.

The supermarket chain’s strong festive performance is tempered by increased costs associated with Covid-19, and the grocer said incremental costs including increased staff absences mean the business anticipates it will incur £810m in additional costs during its current financial year up £85m from its previous October forecast.

As a result of this, Tesco’s full-year forecast remains unchanged and it expects to be at least flat on last year.

Murphy said: “Our focus on looking after our customers, including delivering record availability, robust safety measures and great value has enabled us to maintain strong momentum through the Christmas period, outperforming the market every week.

“We delivered a record Christmas across all of our formats and channels. In response to unprecedented demand for online groceries, colleagues delivered over 7 million orders containing more than 400 million individual items over the Christmas period.  

“We’re now supporting 786,000 vulnerable customers with priority access to online slots and, as lockdown measures continue, we’ll keep doing everything we can to ensure everyone can safely get the food and essentials they need.

“Our colleagues went above and beyond, rising to every challenge in the most exceptional of circumstances and I thank every one of them for this. We’re in great shape to keep delivering in 2021 and beyond.”