GENEVA -- Europe was declared free of poliomyleitis on Friday, marking a major step toward the eradication of the disease in the world by 2005, the World Health Organization (WHO) said on Friday.

"The European region has been certified as free of polio this morning," Bruce Aylward, who coordinator for the polio eradication program told reporters. "The only risk that remains is the accidental release of polio from a laboratory," he added.

The announcement was made after the European Regional Commission for Certification of Poliomyelitis Eradication, an independent body of international public health experts in Copenhagen, decreed that 51 countries in the WHO's European region had been polio free for the required minimum of three years.

But the WHO and the UN Children's Fund (UNICEF) warned that the global polio eradication effort was short of funds and needed 275 million dollars over the next three years to meet its target through vaccination campaigns.

"If we don't raise 60 million dollars for this year, we can't finish the job," Aylward said.

In a document outlining current funding, the WHO noted: "The greatest risk to the polio-free status of Europe is a reintroduction of the virus form remaining polio endemic countries." Last year three children were infected with the disease in Bulgaria and in Georgia, and the cases were thought to have been caused by polio virus originating from the Indian sub-continent, according to WHO.

Ten countries in the world are regarded as polio endemic, several of them countries in conflict where vaccination campaigns have been disrupted.

Conflict in four of the countries in recent years -- Angola, Afghanistan, Sudan and Somalia -- have hampered access to children.

The other polio-endemic countries are Egypt, Ethiopia, India, Nigeria, Niger and Pakistan.

On Friday, WHO and UNICEF announced the start of a three-day immunisation campaign in Angola, taking advantage of a recent peace agreement to target three million children.

Europe is the third geographical region to certify that it has had no indigenous cases for three years, following the Americas, in September 1994, and the western pacific, in October 2000.

"Success in Europe was achieved through an unprecedented series of coordinated national immunisation campaigns, which involved 18 polio endemic countries and areas in the European and east Mediterannean regions," WHO said in a statement.

The only disease which has been eradicated is smallpox, declared officially over by the WHO in 1980.

In the same year, an estimated 500,000 children were paralyzed by polio.

In Afghanistan some of the immunization days that took place during the 1990s brought about a temporary truce in the Central Asian country's civil war to allow children to be vaccinated.