The European Commission announced a ban on all imports of live birds and feathers from Turkey into the 25-nation EU on Monday after Ankara confirmed an outbreak of the highly contagious avian influenza.
But Turkish experts battling the disease played down fears of the kind of epidemic caused by the H5N1 avian influenza virus that has killed millions of birds and 65 people in Asia since 2003. The H5N1 virus is the most deadly of a number of known versions of bird flu.
The Commission said it was taking no steps at the moment over a suspected outbreak of bird flu in Romania.
Results of bird flu tests in Romania and Turkey should be known by Wednesday, October 12, and the Commission would act immediately in accordance with those findings, it said.
"The virological analyses have confirmed that the virus is present (in Turkey) but at the moment we are not able to say what type of virus we are talking about - how pathogenic it is," said Philip Tod, the Commission's health spokesman.
Turkey has so far culled about 3,000 turkeys and chickens after reporting its first outbreak of avian flu at a farm in the district of Manyas, which is near the Aegean and Marmara Seas.
It has clamped a 3-km (2 mile) quarantine zone around the farm, where 1,870 turkeys died of the disease last week. Teams of veterinary experts in white overalls and gloves are hurriedly burying the slaughtered birds in lime-drenched pits.
In a statement urging public calm and vigilance, Turkey's farm ministry said: "Everything is under control."
Romania was also conducting a widespread cull after it detected an outbreak in the Danube delta. Private television station Realitatea TV reported dozens of birds, including swans and poultry, had been found dead in the village of Maliuc in the delta on Monday.
Quarantines were imposed on seven affected Romanian villages, hunting was banned in the delta and the agriculture minister said the country would cull around 45,000 birds.
Bulgaria, sandwiched between Turkey and Romania, announced a ban on imports of poultry and poultry products from its Black Sea neighbours on Monday. Ukraine, which shares a border with Romania, followed suit.
Non-EU member Switzerland also banned poultry imports from Turkey and Romania. Earlier, Hungary announced a ban on Romanian poultry imports and Greece banned imports from Romania and Turkey. Bulgaria, Greece and Hungary beefed up border checks. Turkey's Poultry Producers and Breeders Association said samples of the dead birds had been sent to a specialist laboratory in Britain to identify the strain of the virus. It said the results should be known within a week.