The European Union (EU) has extended its ban on the import of live poultry and fresh poultry products from eight Asian countries until September 30.
Last month the EU's Standing Committee of the Food Chain and Animal Health concluded that Thailand, Cambodia, Indonesia, Laos, China, Vietnam, Pakistan and Malaysia could still not be certified as free of avian influenza.
In Vietnam, the virus has been spreading, despite widespread culling of poultry. The number of human cases of bird flu infection has risen to 11.
The fear is that the virus could mutate to enable human-to-human transmission, causing a human flu pandemic. In Thailand, where at least 12 people have already died from avian flu, the government has proposed multi-million pound emergency procedures to prevent human-to-human transmission.
It plans to spend a reported £66m on fighting the disease over the next 18 months.