"We have received now confirmation that the virus found in Turkey is an avian flu H5N1 virus," said the EU health commissioner, Markos Kyprianou. "There is a direct relationship with viruses found in Russia, Mongolia and China."

Amid growing concerns that a pandemic is imminent, Mr Kyprianou recommended an increased flu vaccination programme for elderly people, children and other vulnerable groups this winter.

Mr Kyprianou also said EU health authorities were considering issuing a warning to people travelling to countries where the disease has been diagnosed, advising them to avoid "going to farms, coming in contact with wild birds and so on".

The European Commission was proposing to set aside €1bn (£680m) to help make and distribute anti-virals and vaccines "in case of a pandemic," he said. EU health ministers will hold urgent talks in the UK next week when they will discuss management of anti-viral stockpiles and other precautions to stop the spread of the virus into the EU, Mr Kyprianou added.

The H5N1 bird flu strain does not easily infect humans, but 117 people, mostly poultry workers living or working in close proximity to infected birds, have caught it over the last two years and at least 60 of them have died.

Carried by wildfowl, the disease spreads quickly among poultry flocks and has broken out in poultry populations in south-east Asian countries including Vietnam, Thailand and Indonesia. Tens of millions of birds have been culled but efforts to contain the disease have not prevented it spreading to the borders of Europe. It was found in the Ural mountains in Russia in August.

On Monday, the EU banned the import of live birds, poultry meat and feathers from Turkey after 1,870 birds died of avian flu in the country last week. A two-mile quarantine zone was imposed around the affected farm and at least 7,600 turkeys have since been culled.

The EU also said tests overnight on samples from birds in Romania have found bird flu and identified the strain as an H5 type virus, but have so far been unable to narrow it down further. Amid the uncertainty, the EU has imposed a ban on imports of poultry from Romania for at least six months.

The World Organisation for Animal Health, meanwhile, said that there is a "high probability" that the bird flu found in Romania is the H5N1 type. It is being taken to Britain for further analysis.

"Confirmation that highly pathogenic avian influenza has been found in Turkey and that Avian influenza is now also in Romania is of concern," said the chief veterinary officer in Britain, Debby Reynolds. "It shows there is a risk to the UK and this is a developing situation, which we are monitoring closely."

Dr Reynolds urged anyone who suspected the disease among birds to report it immediately.

She confirmed that the Turkish samples were brought for analysis to Britain and were taken to the Veterinary Laboratory Agency yesterday morning. They were proved positive at lunchtime today, she said.

Describing the findings as "a substantial development", she added: "This is the first time that this virus - which has been found in Asia, Russia, Mongolia and China - has been found so close to Europe."

Faruk Demirel, spokesman for the Turkish Agriculture Ministry, said the country was prepared for a flu outbreak. "The measures we have already taken were in line with the worst-case scenario," he said.

Turkey has asked the Swiss pharmaceutical company Roche Holding AG for 1m boxes of a standard flu medicine as a precaution against a possible pandemic, an official said.

Two weeks ago, the UN official in charge of coordinating the worldwide response to any flu outbreak warned a pandemic could kill up to 150 million people.

David Nabarro, one of the most senior public health experts at the World Health Organisation, said outbreaks of bird flu could mutate into a form transmissible between people.

"The consequences in terms of human life when the pandemic does start are going to be extraordinary and very damaging," he said. He said that the "range of deaths could be anything between five and 150 million".

In August, Neil Ferguson, a professor of mathematical biology at Imperial College London, told Guardian Unlimited that up to 200 million people could be killed.

"Around 40 million people died in the 1918 Spanish flu outbreak," said Prof Ferguson. "There are six times more people on the planet now so you could scale it up to around 200 million people probably."

A Department of Health contingency plan states that there could be between 21,500 and 709,000 deaths in Britain.

Last month, veterinary and medical chiefs from the European Union held talks aimed at drawing up an EU-wide action plan to prevent the spread of bird flu. Experts say spotting any outbreak immediately and treating local people with anti-viral drugs and vaccines will be the key to containing any outbreak.

Rich countries are stockpiling anti-viral supplies. Britain announced in March that it was spending £200m on treatments for up to 14 million people. In July the government also said it would buy 2m doses of vaccine for key workers, though it will take around six months for it to arrive. The problem facing governments and the WHO is that it is difficult to know what vaccine to produce until an outbreak occurs and then to manufacture treatments in sufficient quantities.

"A flu outbreak is imminent but no one knows if it will be next week or in three years' time," a WHO spokeswoman said last month. "It is really difficult to know how many people will be infected but we know we have to get prepared." She said the "best case scenario" would be 7.4 million deaths globally.