Russia's food safety regulator on Tuesday accused the popular French hypermarket chain Auchan of selling beef and pork mince containing meat from sheep and chicken.

Samples of beef mince were found to contain pig, chicken and sheep DNA, the watchdog Rosselkhoznadzor said in a statement on its website, while pork mince contained DNA from cattle, chicken and sheep.

But the food safety agency did not repeat a claim made only hours earlier that Auchan's pork mince contained horse DNA.

Its press service could not be reached to explain the reason for the change.

The agency said in the statement that its findings "allow the conclusion to be drawn that the food products are falsified by replacing one kind of meat with another that is less expensive."

Contacted by AFP, Auchan Russia spokeswoman Maria Kurnosova said the company "had launched an internal enquiry to check this information and understand the reasons for these violations if they took place."

The latest checks on Auchan came after Rosselkhoznadzor upbraided the company several times over food hygiene.

On July 30, it alleged Auchan was adding extra days to the best-before dates on chilled meat products in its distribution warehouses in the Moscow region.

A day later, the agency published a photo of a pizza in an Auchan store in the Moscow region saying the pepperoni was past its sell-by date.

Auchan has been present in Russia since 2002 and has 88 stores in the country, aimed at those looking to save money on food and household goods.

Russian President Vladimir Putin in June extended an embargo on most food imports from Western countries that had slapped sanctions on Moscow over the Ukraine crisis.