Belgrade, 27 April (AKI) – Serbia has banned pork imports after the outbreak of the deadly swine flu virus that has so far killed at least 100 people in Mexico. More than 1,600 people are believed to have been infected in the country by the virus.

At least 20 cases have been confirmed in the United States and suspected cases have been reported in Spain and France, as well as Israel, Brazil, New Zealand, and Australia.

At least one case of swine fever has been confirmed in Spain.

Serbian authorities said they would be closely monitoring the country's borders for any sign of the virus.

“The borders are relatively safe concerning animals, but not so much where people are concerned,” said Belgrade health official Predrag Kon.

Serbian health minister Tomica Milosavljevic said travellers coming from Mexico should be closely watched for possible flu symptoms.

In neighbouring Bulgaria, passengers are being offered protective masks at the airport in the country's capital, Sofia. Croatian health minister Darko Milinovic warned that there was no reason for panic in Croatia.

Milinovic said his ministry was staying in contact with the European Union and the World Health Organization and closely following developments.

European Union health commissioner Androulla Vassiliou has asked the EU Czech presidency of the EU to urgently organise a meeting of EU health ministers this week to discuss the threat posed to the continent by swine flu and appropriate measures.

The World Health Organization were due to meet on Tuesday at their headquarters in Geneva, Switzerland, to discuss whether to raise the pandemic alert level.

The WHO - the United Nation's health agency - has warned that the swine flu virus may mutate into a more dangerous strain.

There is currently no vaccine for swine flu but severe cases can be treated with antiviral medication.