Up to 20 countries worldwide have banned imports of pork and other meat in response to the swine flu outbreak.
The H1N1 strain is not food-borne, but there are still fears it may spread through animal products.
The European Union, South Korea, Japan all say they will avoid any ban for the time being.
Global trade in pork meat is worth about $US26 billion per year.
Countries identified by the World Health Organisation as having imposed bans include: Russia, China, Croatia, Indonesia, Thailand and Ecuador.
The three countries most affected by the bans - Mexico, the United States and Canada - are among the world's top pork exporters along with the European Union, Brazil, Chile, China and Hong Kong.
Other countries whose exports would be blocked by the bans include: New Zealand, Spain, France, Israel, Costa Rica, El Salvador, Colombia, Cuba, Nicaragua, Panama, Honduras, Guatemala and the Dominican Republic.