Dutch authorities have identified an outbreak of avian flu in chickens at a farm in the centre of the country that is likely a "low risk" strain, officials said Thursday.

"Bird flu has been identified at an egg farm in Barneveld with around 30,000 chickens," the economics ministry said in a statement.

"It is highly likely that it is the mild H7 strain," it said, adding that tests were expected to confirm the strain on Friday.

As the H7 form can mutate into a highly pathogenic strain, all 30,000 birds will be culled, the ministry said.

A three-week ban on transporting poultry has been implemented within a one-kilometre (just over half a mile) radius around the farm, where 17 other poultry farms are being tested.

An outbreak of the highly infectious H5N8 strain hit several Dutch farms in November and December last year, with tens of thousands of birds culled.

Authorities suspected the H5N8 strain might have been brought in by birds migrating from Asia.

The virus has previously hit Europe, South Korea, Taiwan, Japan, Canada and the United States.

Some strains of avian flu are fatal for birds, and pose a threat to humans, who can fall sick after handling infected poultry.