LONDON (AP) — GlaxoSmithKline has received orders from several countries to stockpile pandemic vaccine as soon as it gets the vaccine's key ingredient from the World Health Organization. As the swine flu continues to spread worldwide — WHO says 34 countries have reported more than 7,500 cases — health officials are deciding when to ask vaccine makers to start making a vaccine to fight the virus. "We expect this pattern of spread to continue," said Dr. Margaret Chan, WHO's director-general on Friday, before the U.N. health agency's yearly meeting of its 193 member states. According to WHO's pandemic alert scale, the world is currently in phase 5 of a possible 6, meaning a global flu outbreak is imminent. About a dozen developed countries, including Canada, France and the United States, have struck advance deals with vaccine producers like GlaxoSmithKline PLC and Sanofi Aventis to provide pandemic vaccine as soon as their factories start producing it. WHO will also ask vaccine producers to save a portion of their pandemic vaccines for poor nations. A pandemic vaccine based on the swine flu virus could be available in four to six months, once companies receive the "seed stock" from WHO. That is currently being developed by the U.S. Centers for Disease Control and Prevention, and is expected to be ready in the next few weeks. In a press statement, Glaxo said it had received "interest" from several governments keen to stock swine flu vaccine, including Britain, France, Belgium and Finland. On Thursday, WHO convened a group of vaccine manufacturers and other experts to discuss issues such as when swine flu vaccine production should begin, how many doses will be needed and who should get the vaccines. WHO flu chief Keiji Fukuda said there were no big decisions about swine flu vaccine and that more meetings would be needed before the agency made any recommendations to manufacturers. Next week, WHO's Chan and U.N. Secretary-General Ban Ki-moon will meet with vaccine makers to discuss swine flu issues.