The head of the World Health Organization on Tuesday strongly rejected suggestions that her decisions about swine flu were influenced by advisers' links to pharmaceutical companies.
"At no time, not for one second, did commercial interests enter my decision-making," WHO Director-General Margaret Chan said.
She also dismissed claims the global health body had stirred unnecessary public fear over the pandemic.
Her statement came in response to an article in the British Medical Journal that questioned the way WHO managed conflicts of interest among its scientific advisers and the transparency of its advice to governments.
WHO's handling of the outbreak is being reviewed by a 29-member expert panel that will report its findings next year. Critics say many of the panelists are also trusted WHO advisers and government employees who could end up whitewashing any failures.
The names of the scientists who advised Chan on the threat posed by swine flu have never been published and WHO said they will only be released once the pandemic is declared over.
"Our decision not to make these names public was motivated by a desire to protect the experts from commercial or other influences," Chan said, adding that it was not an attempt to keep the panelists' deliberations secret.
WHO said it will make records of the advisers' meetings available to the review panel but hasn't indicated any willingness to release them publicly.
Chan insisted she was open to the panel's criticism. "Should this committee decide that the current definition of a pandemic and the phases leading up to its declaration need to be tightened or otherwise revised, this will be another recommendation that we will welcome, and act on."
Harvey Fineberg, the president of the Institute of Medicine in Washington, said the review panel which he heads will hear from critics of WHO when it next meets from June 30 to July 2.
A report published by the Council of Europe last week said the public health guidelines by WHO, European Union agencies and national governments led to a "waste of large sums of public money and unjustified scares and fears about the health risks faced by the European public." The report by the EU's human rights watchdog said decisions about the outbreak were poorly explained and not sufficiently transparent.