Eggs imported from Ukraine have tested positive for salmonella amid a major outbreak that has infected at least 650 people in Britain, hospitalised 99 and killed two.

The discovery has triggered an urgent recall after tests found the eggs carried a strain of the bug linked to 36 infections in England this year.

It marks a significant breakthrough in an ongoing investigation, with imported eggs served in restaurants, cafes and takeaways already suspected to be behind the outbreak.

However, health chiefs say the strain found in the recalled eggs is different from those linked to the 650 cases already identified.

Genetic testing revealed that the bacteria found in the Ukrainian eggs matched a strain detected in 36 patients in England this year, but not the three strains behind the wider outbreak.

The findings raise the possibility that investigators have uncovered a separate cluster of infections linked to contaminated imported eggs.

The Food Standards Agency has now ordered all eggs from the Ukrainian producer Yasensvit Ltd, stamped with the code 3UA1012066, to be removed from sale and recalled.

The eggs were mainly supplied to restaurants and other catering businesses, although some may also have been sold in smaller shops. None were sold in major supermarkets.

The recall covers eggs of all sizes and best-before dates bearing the affected code.

The FSA warned that some may have been repackaged in Britain, meaning the details on the outer packaging could be different.

Businesses have been told to immediately stop using or selling the eggs and dispose of any remaining stock, while consumers are urged to check the code stamped on individual eggs and throw away any affected products.

Jacquelyn McCormick, head of incidents at the FSA, said: 'We have identified Salmonella Enteritidis in eggs that were imported from a business in Ukraine and taken urgent action to protect public health.'

She stressed that British-produced eggs were unaffected, adding: 'Eggs bought in major supermarkets are produced in the UK, and therefore not affected by this outbreak.'

Hannah Charles, lead epidemiologist at the UKHSA, said genetic testing had confirmed the presence of Salmonella Enteritidis in the imported eggs.

She said: 'The S. Enteritidis strain we identified in this batch of imported eggs is genetically different to S. Enteritidis strains linked to the ongoing Salmonella outbreak investigation, but is associated with 36 Salmonella cases in England reported in 2026.'

The wider outbreak has continued to grow since it was first reported in July, with hospitalisations more than tripling from 31 to 99 by the beginning of October.

Salmonella typically causes diarrhoea, stomach cramps, vomiting and fever, but in severe cases can trigger life-threatening sepsis.

Young children, older people, pregnant women and those with weakened immune systems are particularly vulnerable.

The FSA said it was continuing to investigate the source of the wider outbreak alongside UKHSA and international partners.