The UK Food Standards Agency (FSA) said that nearly 700,000 Fipronil-contaminated eggs have been imported from Dutch farms, a significant increase from the previously reported 21,000.

The products affected in the UK include processed foods such as sandwich fillings or other chilled foods in which egg is used as an ingredient.

According to the agency, this represents 0.007% of the eggs consumed annually in the country.

The FSA further noted that there was no evidence that eggs laid in the UK are contaminated or that Fipronil has been used inappropriately in the country.

On-site farm testing is currently underway across the country and results so far have not indicated any exposure to the chemical compound in England and Wales.

FSA chairman Heather Hancock said: ‘I’m confident that acting quickly is the right thing to do.

“The number of eggs involved is small in proportion to the number of eggs we eat, and it is very unlikely that there is a risk to public health.

“based on the available evidence there is no need for people to change the way they consume or cook eggs.

“However, Fipronil is not legally allowed for use near food-producing animals and it shouldn’t be there.’

The FSA has identified some of the products made from these eggs, which are being withdrawn by the businesses involved.

Meanwhile, Food Standards Scotland (FSS) has urged food businesses in the country to inform the relevant local authorities immediately if they believe that a product that they have imported, manufactured, processed or distributed does not comply with food safety requirements.

The Danish Veterinary and Food Administration also issued a statement saying that 20t of the contaminated eggs have been sold in Denmark.