The supermarket has claimed pharmaceuticals at a Cardiff store were blocked off due to a break-in.
Tesco has apologised after it suggested sanitary products were “non-essential” and so could not be sold due to new Welsh lockdown measures.
On Sunday, Wales Minister Mark Drakeford said supermarkets have “discretion” over the ban on selling non-essential items during the nation’s firebreak lockdown.
But on Monday, customers seeking period products in St Mellons, Cardiff, said they found the pharmaceuticals area of their local Tesco blocked off.
“I’m literally raging and in tears @Tesco how the hell is beer essential and PERIOD PRODUCTS are non-essential… this is RIDICULOUS,” tweeted @nicholasmith6.
When another customer sent a tweet to the company about the issue, it responded: “We understand how frustrating these changes will be for our Welsh customers.
“However, we have been told by the Welsh Government not to sell these items for the duration of the firebreak lockdown.”
The Welsh Government later corrected Tesco, tweeting: “This is wrong – period products are essential.
“Supermarkets can still sell items that can be sold in pharmacies.
“Only selling essential items during firebreak is to discourage spending more time than necessary in shops. It should not stop you accessing items that you need.”
The company has now apologised, adding that the issue was localised to one store and has been rectified.
It also claimed that the pharmaceuticals area of the St Mellons store was actually cordoned off due to a break-in.
South Wales Police said officers are investigating a burglary at the supermarket in which £20,000 of beauty products, including make-up, electric toothbrushes and razors, were stolen between 2.30am and 4.30am on Monday.
“Of course sanitary products are essential items and are available to customers in all of our stores, including those in Wales,” a Tesco spokesman said.
“Due to a break-in, this area was closed temporarily in one store for a police investigation, but is now open again.
“The reply to this customer, which implied these products were non-essential, was sent by mistake and we’re very sorry for any confusion caused.”
Welsh Conservative health spokesman Andrew RT Davies said the confusion was the result of a “barmy ban” by the Welsh Labour Government which should be stopped.
“No woman should be put through such an experience and sadly this chaos and confusion is a direct result of the Welsh Labour Government’s barmy ban on non-essential retail,” Mr Davies said.
“This ludicrous policy has caused real anger and it’s not fair on staff working in our supermarkets and the general Welsh public who are now at their wits’ end with Labour ministers.
“The Welsh Labour Government has rushed out a policy that was not even understood by the country’s largest supermarket and that’s the fault of the First Minister and his colleagues.
“This ban must be dropped today.”