Shares in Tesco rose on Tuesday after industry data showed Britain's biggest retailer had gained its highest market share since February 2019, though the threat of pre-Christmas strikes has escalated.
The stock was up 1% at 11:47 GMT, extending 2020 gains to 23% after market researcher Kantar showed Tesco significantly outperformed its main rivals - Sainsbury's, Asda and Morrisons - in the 12 weeks to 28 November, winning 0.7 percentage points of market share in the period, its biggest jump since 2007.
'Potential Strike Action'
While the data showed Tesco leading the pack going into the key Christmas period, a cloud on the horizon is potential strike action which could hit product availability in stores.
Tesco was already facing strikes by Unite union workers at four distribution centres in a dispute over pay.
It is now facing walkouts by over 5,000 members of the Usdaw union at a further nine depots - Daventry, Peterborough, Hinckley and Lichfield in central England, Goole in northern England, Southampton in southern England, Livingston in Scotland and Magor in Wales.
The Usdaw members will strike from 20 December to 24 December.
Both unions have rejected Tesco's offer of a 4% annual pay increase.
'Ready To Reopen Negotiations'
“Industrial action and possible stock shortages in stores in the week before Christmas can be avoided. It needs the company to engage positively in talks with Usdaw and we stand ready to reopen negotiations," said Usdaw National Officer, Joanne McGuinness.
Tesco says it has had made a fair pay offer and has plans in place to help mitigate any impacts.
British retailers are already grappling with delays in international supply chains that are being compounded by labour shortages in domestic transport and warehousing networks, with a lack of heavy goods vehicle (HGV) drivers particularly acute.
However, Tesco said in October it was coping well.