European vets today gave approval to controversial applications from France and the Netherlands to vaccinate selected poultry flocks against avian flu, a ruling with profound implications for the rest of the EU.

After two days of heated talks the European Commission, the EU's executive body, agreed to the requests with a series of conditions.

"The vaccination programmes are authorised only for specific birds in specified regions, and will be subject to rigorous surveillance and control requirements," the Commission said in a statement from Brussels.

"These include movement restrictions, strict monitoring of vaccinated flocks to ensure that there is no undetected outbreak of avian influenza, and careful record-keeping."

The move signifies an important ratcheting-up in the Continent's disease control. Under European law, any vaccinated birds would face restrictions on movement which would prevent export and allow them only to be transported to a slaughterhouse.

The French and Dutch proposals were the first of their kind to be submitted to Brussels and are aimed at preventing bird flu spreading from wild migratory birds to domestic fowl.

Britain continues to oppose the vaccination programme on grounds of both cost and effectiveness, as do Germany, Austria, Denmark and Portugal.

Vaccinated birds could incubate the disease without showing symptoms, allowing low-level spread among flocks and increasing the likelihood of its mutation into a form transmissible to people.

The sense of urgency was heightened today as Austria reported the EU's first cases of the lethal H5N1 strain in domestic fowl rather than wild birds.

The regional agriculture minister revealed that a swan, two chickens and three ducks had been found carrying the virus at a sanctuary in the southern city of Graz.

It was reported that the rescue fowl had been kept in the same cage as infected swans brought to the Noah's Ark shelter for abandoned animals following an outbreak last week.

Slovakia yesterday became the eighth EU member state to confirm the presence of bird flu in migrating fowl. It joins Italy, Greece, France, Slovenia, Austria, Germany and Hungary as states where the H5N1 strain has been detected.

France wants to inoculate some 900,000 geese and ducks in three districts in a £500,000 programme that would start immediately and continue until April.

The Netherlands - devastated in 2003 by an H7N7 bird flu outbreak that forced the slaughter of a quarter of its agricultural fowl - is looking to vaccinate five million backyard birds and free-range laying hens nationwide.

The Dutch plan would be conducted on a voluntary basis as an alternative to demands that poultry be kept indoors.

More than 90 people have died from bird flu in Asia, Iraq and eastern Turkey since 2003 after contracting the potentially lethal H5N1 strain from infected poultry but no human infections have been reported in Europe.