A policeman removes a check point notice from the road to the village where bird flu patient were found in Zhongwei County, northwest Ningxia Autonomous Region, August 12, 2006. [Xinhua]

"This is groundless and irresponsible," sources with the ministry's press office told China Daily on Friday.

According to the current information held by the Chinese authorities, a verdict arrived at by the United Nations Food and Agriculture Organization (FAO) and the bird flu research and test centre of Thailand was arbitrary and based on the fact that the virus found in Thailand and Laos was similar to recent finds in southern China, the ministry's statement said.

The ministry has not found the full text of the test report by the FAO and the Thai centre and knew little about the test procedure, and origin and type of the examples used.

However some media reports quoted the FAO conclusion and correlated the outbreak in Thailand with southern China.

According to statistics provided by China's customs, the country has not exported any poultry products to Thailand or Laos since 2004 when China first reported a H5N1 outbreak in its poultry.

"Nakhon Phanom in Thailand and the Laotian capital of Vientiane, where the virus strain was detected, are both very far from the Chinese border," the ministry's statement said.

In conclusion, the ministry denied the possibility that the virus was transmitted through poultry trade across the borders, as was mentioned in several foreign reports.

The ministry emphasized that as the prevention and control abilities of different Asian countries varied, most reports were inconclusive and could not safely be used to detect new trends.

Also complicating the case is the fact that the virus can be transmitted by wild birds.

"So it is irresponsible to decide that the strain of virus detected in Thailand was from a certain country before having sufficient evidence," the statement said.

The ministry said that as a responsible country, China was ready to co-operate with all countries in to fight against the bird flu epidemic.